scripts: replace /bin/bash by /usr/bin/env bash

Test Plan: Set up environment locally; CI

X-Origin-Diff: phab/D759
GitOrigin-RevId: 01142b03dcfb44c1dcb42169cc9af187c1518107
diff --git a/scripts/bin/bazel b/scripts/bin/bazel
index 535eda5..1fda28c 100755
--- a/scripts/bin/bazel
+++ b/scripts/bin/bazel
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 set -euo pipefail
 
 # Override the intellij_aspect repository to point to our own copy that create_container.sh has applied patches to.