Merge #13454: Make sure LC_ALL=C is set in all shell scripts

47776a958b Add linter: Make sure all shell scripts opt out of locale dependence using "export LC_ALL=C" (practicalswift)
3352da8da1 Add "export LC_ALL=C" to all shell scripts (practicalswift)

Pull request description:

  ~~Make sure `LC_ALL=C` is set when using `grep` range expressions.~~

  Make sure `LC_ALL=C` is set in all shell scripts.

  From the `grep(1)` documentation:

  > Within a bracket expression, a range expression consists of two characters separated by a hyphen. It matches any single character that sorts between the two characters, inclusive, using the locale's collating sequence and character set. For example, in the default C locale, `[a-d]` is equivalent to `[abcd]`. Many  locales sort characters in dictionary order, and in these locales `[a-d]` is typically not equivalent to `[abcd]`; it might be equivalent to `[aBbCcDd]`, for example. To obtain the traditional interpretation of bracket expressions, you can use the C locale by setting the `LC_ALL` environment variable to the value C.

  Context: [Locale issue found when reviewing #13450](https://github.com/bitcoin/bitcoin/pull/13450/files#r194877736)

Tree-SHA512: fd74d2612998f9b49ef9be24410e505d8c842716f84d085157fc7f9799d40e8a7b4969de783afcf99b7fae4f91bbb4559651f7dd6578a6a081a50bdea29f0909

contrib/verify-commits/gpg.sh

@@ -3,6 +3,7 @@
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+export LC_ALL=C
 INPUT=$(cat /dev/stdin)
 VALID=false
 REVSIG=false