Add revisions to safe/unsafe on unadorned extern blocks test

Author: spastorino

tests/ui/rust-2024/unsafe-extern-blocks/safe-unsafe-on-unadorned-extern-block.stderr renamed to tests/ui/rust-2024/unsafe-extern-blocks/safe-unsafe-on-unadorned-extern-block.edition2021.stderr

@@ -1,13 +1,14 @@
 error: items in unadorned `extern` blocks cannot have safety qualifiers
-  --> $DIR/safe-unsafe-on-unadorned-extern-block.rs:2:5
+  --> $DIR/safe-unsafe-on-unadorned-extern-block.rs:10:5
    |
 LL | extern "C" {
    | ---------- help: add unsafe to this `extern` block
+LL |
 LL |     safe static TEST1: i32;
    |     ^^^^^^^^^^^^^^^^^^^^^^^
 
 error: items in unadorned `extern` blocks cannot have safety qualifiers
-  --> $DIR/safe-unsafe-on-unadorned-extern-block.rs:4:5
+  --> $DIR/safe-unsafe-on-unadorned-extern-block.rs:12:5
    |
 LL | extern "C" {
    | ---------- help: add unsafe to this `extern` block

tests/ui/rust-2024/unsafe-extern-blocks/safe-unsafe-on-unadorned-extern-block.edition2024.stderr

@@ -0,0 +1,32 @@
+error: extern blocks must be unsafe
+  --> $DIR/safe-unsafe-on-unadorned-extern-block.rs:8:1
+   |
+LL | / extern "C" {
+LL | |
+LL | |     safe static TEST1: i32;
+LL | |
+LL | |     safe fn test1(i: i32);
+LL | |
+LL | | }
+   | |_^
+
+error: items in unadorned `extern` blocks cannot have safety qualifiers
+  --> $DIR/safe-unsafe-on-unadorned-extern-block.rs:10:5
+   |
+LL | extern "C" {
+   | ---------- help: add unsafe to this `extern` block
+LL |
+LL |     safe static TEST1: i32;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^
+
+error: items in unadorned `extern` blocks cannot have safety qualifiers
+  --> $DIR/safe-unsafe-on-unadorned-extern-block.rs:12:5
+   |
+LL | extern "C" {
+   | ---------- help: add unsafe to this `extern` block
+...
+LL |     safe fn test1(i: i32);
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 3 previous errors
+

tests/ui/rust-2024/unsafe-extern-blocks/safe-unsafe-on-unadorned-extern-block.rs

@@ -1,4 +1,12 @@
+//@ revisions: edition2021 edition2024
+//@[edition2021] edition:2021
+//@[edition2024] edition:2024
+//@[edition2024] compile-flags: -Zunstable-options
+
+#![feature(unsafe_extern_blocks)]
+
 extern "C" {
+    //[edition2024]~^ ERROR extern blocks must be unsafe
     safe static TEST1: i32;
     //~^ ERROR items in unadorned `extern` blocks cannot have safety qualifiers
     safe fn test1(i: i32);