Update tests for excess semicolon lint

Author: nathanwhit

src/test/ui/block-expr-precedence.stderr

@@ -0,0 +1,8 @@
+warning: unnecessary trailing semicolons
+  --> $DIR/block-expr-precedence.rs:60:21
+   |
+LL |   if (true) { 12; };;; -num;
+   |                     ^^ help: remove these semicolons
+   |
+   = note: `#[warn(redundant_semicolon)]` on by default
+

src/test/ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.stderr

@@ -28,7 +28,10 @@ error: expected `{`, found `;`
 LL |     if not  // lack of braces is [sic]
    |     -- this `if` statement has a condition, but no block
 LL |         println!("Then when?");
-   |                               ^ expected `{`
+   |                               ^
+   |                               |
+   |                               expected `{`
+   |                               help: try placing this code inside a block: `{ ; }`
 
 error: unexpected `2` after identifier
   --> $DIR/issue-46836-identifier-not-instead-of-negation.rs:26:24

src/test/ui/parser/doc-before-semi.rs

@@ -3,4 +3,6 @@ fn main() {
     //~^ ERROR found a documentation comment that doesn't document anything
     //~| HELP maybe a comment was intended
     ;
+    //~^ WARNING unnecessary trailing semicolon
+    //~| HELP remove this semicolon
 }

src/test/ui/parser/doc-before-semi.stderr

@@ -6,6 +6,14 @@ LL |     /// hi
    |
    = help: doc comments must come before what they document, maybe a comment was intended with `//`?
 
+warning: unnecessary trailing semicolon
+  --> $DIR/doc-before-semi.rs:5:5
+   |
+LL |     ;
+   |     ^ help: remove this semicolon
+   |
+   = note: `#[warn(redundant_semicolon)]` on by default
+
 error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0585`.

src/test/ui/proc-macro/span-preservation.rs

@@ -9,7 +9,7 @@ extern crate test_macros;
 
 #[recollect_attr]
 fn a() {
-    let x: usize = "hello";;;;; //~ ERROR mismatched types
+    let x: usize = "hello"; //~ ERROR mismatched types
 }
 
 #[recollect_attr]

src/test/ui/proc-macro/span-preservation.stderr

@@ -6,7 +6,7 @@ error[E0308]: mismatched types
 error[E0308]: mismatched types
   --> $DIR/span-preservation.rs:12:20
    |
-LL |     let x: usize = "hello";;;;;
+LL |     let x: usize = "hello";
    |                    ^^^^^^^ expected usize, found reference
    |
    = note: expected type `usize`