Auto merge of #97892 - klensy:fix-spaces, r=oli-obk

diagnostics: remove trailing spaces

Remove few occurrences of trailing spaces and drive by fix of needless alloc of const string.

diff --cc compiler/rustc_errors/src/emitter.rs
Simple merge

diff --cc src/test/ui/imports/issue-59764.stderr
Simple merge

diff --cc src/test/ui/parser/recover-labeled-non-block-expr.stderr
Simple merge