Auto merge of #7945 - pierrechevalier83:fix_issue_7914, r=jdm

Refactor away unnecessary use of regex

We don't need regex matching since ": &Vec<" doesn't
contain any special character.

New code reads better.

Fixes #7914.

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python/tidy.py

@@ -351,7 +351,7 @@ def check_rust(file_name, contents):
             mods = []
 
         # There should not be any extra pointer dereferencing
-        if re.search(r": &Vec<", line) is not None:
+        if ": &Vec<" in line:
             yield (idx + 1, "use &[T] instead of &Vec<T>")