pre-commit 2.16.0 switched from Python to bash in the hooks installed to .git/hooks. We're patching hook scripts to activate the virtualenv for the pre-commit Nox session. This PR teaches the Nox session to detect bash hooks. The inserted fragment for virtualenv activation was ported to bash.

This PR also fixes a potential crash when files in the hook directory cannot be opened using the default text encoding. We're now checking that the binary file contents start with the shebang sequence #! before attempting to decode the contents. That should at least deal with binaries. Scripts with random garbage will still cause the hook installation to crash.

• 🔨 Split conditional
• 🔨 Replace if not continue with if
• ✨ Add bash version
• 🔨 Add comments with pre-commit version ranges
• 🔨 Extract variable patches
• 🔨 Move bash fragment into patches
• 🔨 Slide comments
• 🔨 Replace if...elif with for...if...break loop over patches
• 🔨 Do not duplicate patches keys
• 🔨 Inline variable header
• 🔨 Rename variable patches to headers
• 🔨 Rename variable patch to header
• 🔨 Support multiple languages when checking for bindir
• ✨ Support bash when checking for bindir
• 🔨 Slide bindirs before loop
• 🐛 Fix over-aggressive quote removal for bindir in bash hooks
• 🔨 Inline variable bindirs into bindirs
• 💡 Expand comment
• 🔨 Slide headers before loop
• 🔨 Replace lines[0].startswith with hook.read_bytes().startswith
• 🐛 Do not attempt to decode hooks unless they have a shebang