Thank you Dylan and JohnTitor for blessing me.

src/test/ui/dollar-crate/dollar-crate-is-keyword.rs

@@ -8,6 +8,7 @@ macro_rules! m {
 
         use $crate; //~ ERROR `$crate` may not be imported
         use $crate as $crate; //~ ERROR expected identifier, found reserved identifier `$crate`
+        //~^ ERROR `$crate` may not be imported
     }
 }
 

src/test/ui/dollar-crate/dollar-crate-is-keyword.stderr

@@ -19,7 +19,7 @@ LL | m!();
 error: `$crate` may not be imported
   --> $DIR/dollar-crate-is-keyword.rs:9:9
    |
-LL |         use $crate; // ERROR `$crate` may not be imported
+LL |         use $crate;
    |         ^^^^^^^^^^^
 ...
 LL | m!();
@@ -35,4 +35,3 @@ LL | m!();
    | ----- in this macro invocation
 
 error: aborting due to 4 previous errors
-

src/test/ui/imports/import-crate-var.stderr

@@ -1,8 +1,9 @@
 error: `$crate` may not be imported
-  --> $DIR/import-crate-var.rs:7:5
+  --> $DIR/import-crate-var.rs:6:5
    |
 LL |     m!();
    |     ^^^^^
    |
-   = note: this warning originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
+   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
 
+error: aborting due to previous error