[clang-tools-extra] [clang-tidy][NFC][doc] improve "options" sections of `bugprone-` and `modernize-` checks (PR #133525)

[Carlos Galvez via cfe-commits]

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@@ -163,7 +163,11 @@ Options
     Semicolon-separated list of containers without their template parameters
     and some ``emplace``-like method of the container. Example:
     ``vector::emplace_back``. Those methods will be checked for improper use and
-    the check will report when a temporary is unnecessarily created.
+    the check will report when a temporary is unnecessarily created. Default
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carlosgalvezp wrote:

Since this is a semicolon-separated list of strings, we typically write: "Default is ``vector;deque;forward_list...``". This helps the user understand what format they should use if they'd like to use something else.

https://github.com/llvm/llvm-project/pull/133525