xfstests: Convert all tests to use /bin/bash

While most tests use /bin/sh, they are dependent on /bin/sh being a
bash shell.  Convert all the tests to execute via /bin/bash as it is
much, much simpler than trying to debug and remove all the bashisms
throughout the test code.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>

051

@@ -1,4 +1,4 @@
-#! /bin/sh
+#! /bin/bash
 # FS QA Test No. 051
 #
 # Test out ACLs.
@@ -100,7 +100,7 @@ echo "Setup file"
 #       in order to execute it.
 touch file1
 cat <<EOF >file1
-#!/bin/sh
+#!/bin/bash
 echo "Test was executed"
 EOF
 chmod u=rwx file1