fix: Set bash as the interpretter for bash-hook command

[kamilogorek]

Shell script produced by bash-hook was missing a shebang, which caused it to be executed by sh in some environments. And because sh has no process substitution (https://www.shellcheck.net/wiki/SC3001) it failed with a syntax error.

Fixes https://github.com/getsentry/sentry-cli/issues/1260

[kamilogorek]

@mitsuhiko not sure what's reliable way of detecting used interpreter

[kamilogorek]

How would $SHELL tell you that you are not using sh? 🤔

[github-actions[bot]]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[kamilogorek]

This wont work, so cleaning it up for now.