Use portable shebang (#!/usr/bin/env bash) for bash scripts (#542)

Replace #!/bin/bash with #!/usr/bin/env bash for portability across
systems where bash may not be installed at /bin/bash (e.g. NixOS,
some BSDs, non-standard installations).

Generated-by: Claude <noreply@anthropic.com>

Signed-off-by: Taylor Howard <taylorhoward@me.com>
(cherry picked from commit d67ce48)

Author: taylorhoward92

examples/test_c_child_requires_c_no_deps.bash

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 TEST_STATUS=0
 
 echo

test/cmake_minimum_required.bash

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # Verify that cmake_minimum_required statements have matching version numbers
 
 export CMAKE_FILES_TO_CHECK="