diagnostics: remove inconsistent English article "this" from E0107

Consider `tests/ui/const-generics/generic_const_exprs/issue-102768.stderr`,
the error message where it gives additional notes about where the associated
type is defined, and how the dead code lint doesn't have an article,
like in `tests/ui/lint/dead-code/issue-85255.stderr`. They don't have
articles, so it seems unnecessary to have one here.

Author: notriddle

compiler/rustc_hir_analysis/src/structured_errors/wrong_number_of_generic_args.rs

@@ -462,7 +462,7 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> {
 
         if self.gen_args.span_ext().is_some() {
             format!(
-                "this {} takes {}{} {} argument{} but {} {} supplied",
+                "{} takes {}{} {} argument{} but {} {} supplied",
                 def_kind,
                 quantifier,
                 bound,

tests/ui/argument-suggestions/issue-100154.stderr

@@ -1,4 +1,4 @@
-error[E0107]: this function takes 0 generic arguments but 1 generic argument was supplied
+error[E0107]: function takes 0 generic arguments but 1 generic argument was supplied
   --> $DIR/issue-100154.rs:4:5
    |
 LL |     foo::<()>(());

tests/ui/async-await/issues/issue-65159.rs

@@ -3,7 +3,7 @@
 // edition:2018
 
 async fn copy() -> Result<()>
-//~^ ERROR this enum takes 2 generic arguments
+//~^ ERROR enum takes 2 generic arguments
 {
     Ok(())
 }

tests/ui/async-await/issues/issue-65159.stderr

@@ -1,4 +1,4 @@
-error[E0107]: this enum takes 2 generic arguments but 1 generic argument was supplied
+error[E0107]: enum takes 2 generic arguments but 1 generic argument was supplied
   --> $DIR/issue-65159.rs:5:20
    |
 LL | async fn copy() -> Result<()>

tests/ui/borrowck/issue-82126-mismatched-subst-and-hir.rs

@@ -14,8 +14,8 @@ impl MarketMultiplier {
 }
 
 async fn buy_lock(generator: &Mutex<MarketMultiplier>) -> LockedMarket<'_> {
-    //~^ ERROR this struct takes 0 lifetime arguments but 1 lifetime argument was supplied
-    //~^^ ERROR this struct takes 1 generic argument but 0 generic arguments were supplied
+    //~^ ERROR struct takes 0 lifetime arguments but 1 lifetime argument was supplied
+    //~^^ ERROR struct takes 1 generic argument but 0 generic arguments were supplied
     LockedMarket(generator.lock().unwrap().buy())
 }
 

tests/ui/borrowck/issue-82126-mismatched-subst-and-hir.stderr

@@ -1,4 +1,4 @@
-error[E0107]: this struct takes 0 lifetime arguments but 1 lifetime argument was supplied
+error[E0107]: struct takes 0 lifetime arguments but 1 lifetime argument was supplied
   --> $DIR/issue-82126-mismatched-subst-and-hir.rs:16:59
    |
 LL | async fn buy_lock(generator: &Mutex<MarketMultiplier>) -> LockedMarket<'_> {
@@ -12,7 +12,7 @@ note: struct defined here, with 0 lifetime parameters
 LL | struct LockedMarket<T>(T);
    |        ^^^^^^^^^^^^
 
-error[E0107]: this struct takes 1 generic argument but 0 generic arguments were supplied
+error[E0107]: struct takes 1 generic argument but 0 generic arguments were supplied
   --> $DIR/issue-82126-mismatched-subst-and-hir.rs:16:59
    |
 LL | async fn buy_lock(generator: &Mutex<MarketMultiplier>) -> LockedMarket<'_> {

tests/ui/const-generics/generic_const_exprs/issue-102768.rs

@@ -7,8 +7,8 @@ trait X {
 
 const _: () = {
     fn f2<'a>(arg: Box<dyn X<Y<1> = &'a ()>>) {}
-    //~^ ERROR this associated type takes 1 lifetime argument but 0 lifetime arguments
-    //~| ERROR this associated type takes 0 generic arguments but 1 generic argument
+    //~^ ERROR associated type takes 1 lifetime argument but 0 lifetime arguments
+    //~| ERROR associated type takes 0 generic arguments but 1 generic argument
 };
 
 fn main() {}

tests/ui/const-generics/generic_const_exprs/issue-102768.stderr

@@ -1,4 +1,4 @@
-error[E0107]: this associated type takes 1 lifetime argument but 0 lifetime arguments were supplied
+error[E0107]: associated type takes 1 lifetime argument but 0 lifetime arguments were supplied
   --> $DIR/issue-102768.rs:9:30
    |
 LL |     fn f2<'a>(arg: Box<dyn X<Y<1> = &'a ()>>) {}
@@ -14,7 +14,7 @@ help: add missing lifetime argument
 LL |     fn f2<'a>(arg: Box<dyn X<Y<'_, 1> = &'a ()>>) {}
    |                                +++
 
-error[E0107]: this associated type takes 0 generic arguments but 1 generic argument was supplied
+error[E0107]: associated type takes 0 generic arguments but 1 generic argument was supplied
   --> $DIR/issue-102768.rs:9:30
    |
 LL |     fn f2<'a>(arg: Box<dyn X<Y<1> = &'a ()>>) {}

tests/ui/const-generics/generic_const_exprs/issue-76595.stderr

@@ -1,4 +1,4 @@
-error[E0107]: this function takes 2 generic arguments but 1 generic argument was supplied
+error[E0107]: function takes 2 generic arguments but 1 generic argument was supplied
   --> $DIR/issue-76595.rs:15:5
    |
 LL |     test::<2>();

tests/ui/const-generics/incorrect-number-of-const-args.stderr

@@ -1,4 +1,4 @@
-error[E0107]: this function takes 2 generic arguments but 1 generic argument was supplied
+error[E0107]: function takes 2 generic arguments but 1 generic argument was supplied
   --> $DIR/incorrect-number-of-const-args.rs:6:5
    |
 LL |     foo::<0>();
@@ -16,7 +16,7 @@ help: add missing generic argument
 LL |     foo::<0, Y>();
    |            +++
 
-error[E0107]: this function takes 2 generic arguments but 3 generic arguments were supplied
+error[E0107]: function takes 2 generic arguments but 3 generic arguments were supplied
   --> $DIR/incorrect-number-of-const-args.rs:9:5
    |
 LL |     foo::<0, 0, 0>();