Documentation for new -W regex support fails to mention length requirement

Documentation

-W will now support regex. The documentation says that “If it starts and ends with a forward slash (/)” the message field will be a regular expression. This is incorrect, there is an additional requirement that the field be at least two characters long. / is one character long and starts and ends with a forward slash, but it is not interpreted as a regex (it matches literal /).

Linked PRs

• gh-147969

首先找到關於 -W 新正規表示式支援的 CPython 文件，並閱讀其中關於以斜線開頭和結尾的欄位的措辭。將其與 issue 的長度要求進行比較；當文件準確描述這兩個條件時，工作就完成了。