Parse bang macro as a statement when used in trailing expr position

cc #33953

Currently, the following code produces an error

```rust
fn main() {
    macro_rules! a {
        ($e:expr) => { $e; }
    }
    a!(true)
}
```

With this change, it now compiles, since we parse `a!(true)` as a
statement.

Author: Aaron1011

compiler/rustc_parse/src/parser/stmt.rs

@@ -105,7 +105,10 @@ impl<'a> Parser<'a> {
 
         let mac = MacCall { path, args, prior_type_ascription: self.last_type_ascription };
 
-        let kind = if delim == token::Brace || self.token == token::Semi || self.token == token::Eof
+        let kind = if delim == token::Brace
+            || self.token == token::Semi
+            || self.token == token::Eof
+            || self.token == token::CloseDelim(token::Brace)
         {
             StmtKind::MacCall(P(MacCallStmt { mac, style, attrs }))
         } else {

src/test/ui/macros/bang-macro-stmt.rs

@@ -0,0 +1,12 @@
+// check-pass
+
+// Tests that we parse a bang macro
+// as a statement when it occurs in the trailing expression position,
+// which allows it to expand to a statement
+
+fn main() {
+    macro_rules! a {
+        ($e:expr) => { $e; }
+    }
+    a!(true)
+}

src/test/ui/macros/issue-34421-mac-expr-bad-stmt-good-add-semi.rs

@@ -1,8 +1,9 @@
+// check-pass
+
 macro_rules! make_item {
     ($a:ident) => {
         struct $a;
-    }; //~^ ERROR expected expression
-       //~| ERROR expected expression
+    };
 }
 
 fn a() {

src/test/ui/macros/issue-34421-mac-expr-bad-stmt-good-add-semi.stderr

@@ -1,8 +1,9 @@
+// check-pass
+
 macro_rules! empty { () => () }
 
 fn main() {
     match 42 {
         _ => { empty!() }
-//~^ ERROR macro expansion ends with an incomplete expression
     };
 }

src/test/ui/macros/macro-in-expression-context-2.rs

@@ -1,15 +1,12 @@
-// run-rustfix
+// check-pass
 
 macro_rules! foo {
     () => {
         assert_eq!("A", "A");
         assert_eq!("B", "B");
     }
-    //~^^ ERROR macro expansion ignores token `assert_eq` and any following
-    //~| NOTE the usage of `foo!` is likely invalid in expression context
 }
 
 fn main() {
     foo!()
-    //~^ NOTE caused by the macro expansion here
 }

src/test/ui/macros/macro-in-expression-context-2.stderr

@@ -8,8 +8,6 @@ use attr_stmt_expr::{expect_let, expect_print_stmt, expect_expr, expect_print_ex
 fn print_str(string: &'static str) {
     // macros are handled a bit differently
     #[expect_print_expr]
-    //~^ ERROR attributes on expressions are experimental
-    //~| HELP add `#![feature(stmt_expr_attributes)]` to the crate attributes to enable
     println!("{}", string)
 }
 

src/test/ui/macros/macro-in-expression-context.fixed

@@ -1,21 +1,12 @@
 error[E0658]: attributes on expressions are experimental
-  --> $DIR/attr-stmt-expr.rs:10:5
-   |
-LL |     #[expect_print_expr]
-   |     ^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: see issue #15701 <https://github.com/rust-lang/rust/issues/15701> for more information
-   = help: add `#![feature(stmt_expr_attributes)]` to the crate attributes to enable
-
-error[E0658]: attributes on expressions are experimental
-  --> $DIR/attr-stmt-expr.rs:23:5
+  --> $DIR/attr-stmt-expr.rs:21:5
    |
 LL |     #[expect_expr]
    |     ^^^^^^^^^^^^^^
    |
    = note: see issue #15701 <https://github.com/rust-lang/rust/issues/15701> for more information
    = help: add `#![feature(stmt_expr_attributes)]` to the crate attributes to enable
 
-error: aborting due to 2 previous errors
+error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0658`.