rust: don't escape spaces in regex

Spaces are not in fact a regex special character, and escaping them is
not correct.

rust/hg-core/src/filepatterns.rs

@@ -642,7 +642,7 b' mod tests {'
         // All escape codes
         assert_eq!(
             escape_pattern(br#"()[]{}?*+-|^$\\.&~# \t\n\r\v\f"#),
-            br#"\(\)\[\]\{\}\?\*\+\-\|\^\$\\\\\.\&\~\#\ \\t\\n\\r\\v\\f"#
+            br#"\(\)\[\]\{\}\?\*\+\-\|\^\$\\\\\.\&\~\#\\t\\n\\r\\v\\f"#
                 .to_vec()
         );
     }