[clang-tools-extra] [clang-tidy][readability-identifier-length] refactoring and cleanup (PR #194610)

[Victor Chernyakin via cfe-commits]

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@@ -4,9 +4,9 @@ readability-identifier-length
 =============================
 
 This check finds variables and function parameters whose length are too short.
-The desired name length is configurable.
-
-Special cases are supported for loop counters and for exception variable names.
+The desired name length is configurable. Special short names which should be
+ignored can be specified. Local variables with short names can also be ignored
+if they are short-lived. This check offers no automated fix.
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localspook wrote:

This is unnecessary IMO, no fix-it is implied.
```suggestion
if they are short-lived.
```

https://github.com/llvm/llvm-project/pull/194610