Change shebang of pre-commit-clang-format hook to make it portable

The default one is "#!/bin/bash", but BSD systems doesn't have bash
in that path. For portability reasons, it should be changed to
"#!/usr/bin/env bash".

More info: https://en.wikipedia.org/wiki/Shebang_%28Unix%29#Portability

misc/hooks/pre-commit-clang-format

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 # git pre-commit hook that runs a clang-format stylecheck.
 # Features: