Update taskgroup_cancelAll_from_child test to use new diagnostic

Author: angela-laar

lib/Sema/TypeCheckConcurrency.cpp

@@ -2556,8 +2556,8 @@ namespace {
         if (auto param =  dyn_cast<ParamDecl>(value)){
           if(param->isInOut()){
               ctx.Diags.diagnose(loc, diag::concurrent_access_of_inout_param, param->getName());
+              return true;
           }
-          return true;
         }
 
         // Otherwise, we have concurrent access. Complain.

test/Concurrency/taskgroup_cancelAll_from_child.swift

@@ -13,7 +13,8 @@ func test_taskGroup_cancelAll() async {
 
        group.spawn {
          group.cancelAll() //expected-warning{{capture of 'group' with non-sendable type 'TaskGroup<Int>' in a `@Sendable` closure}}
-                           //expected-error@-1{{reference to captured parameter 'group' in concurrently-executing code}}
+                           //expected-error@-1{{mutable capture of 'inout' parameter 'group' is not allowed in concurrently-executing code}}
+
          return 0
        }
        group.spawn { [group] in