Bug: git grep --no-index 123 /dev/stdin crashes with SIGABRT

Thank you for filling out a Git bug report! Please answer the following questions to help us understand your issue.

What did you do before the bug happened? (Steps to reproduce your issue) `git grep --no-index 123 /dev/stdin` outside of git repository

What did you expect to happen? (Expected behavior) Ability to grep input from stdin

What happened instead? (Actual behavior) `git grep` crashed with SIGABRT

$ git grep --no-index 123 /dev/stdin
BUG: environment.c:215: git environment hasn't been setup
Aborted (core dumped)

What's different between what you expected and what actually happened? Crash, no grep result

Anything else you want to add: Plain grep can do that, so I suppose `git grep` could also:

$ echo -e "123\n456\n789" | grep 456 /dev/stdin 456

Please review the rest of the bug report below. You can delete any lines you don't wish to share.

[System Info] git version: git version 2.41.0 cpu: x86_64 no commit associated with this build sizeof-long: 8 sizeof-size_t: 8 shell-path: /bin/sh uname: Linux 6.5.6-200.fc38.x86_64 #1 SMP PREEMPT_DYNAMIC Fri Oct 6 19:02:35 UTC 2023 x86_64 compiler info: gnuc: 13.1 libc info: glibc: 2.37 $SHELL (typically, interactive shell): /bin/bash

[Enabled Hooks] not run from a git repository - no hooks to show