gtest: Install the run_with_tmp script for convenience

This makes it possible for other tests to utilize the script.

Change-Id: I1bb6100e4018bad020817d569294704e267c2776
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/test/meson.build b/test/meson.build
index 1f284a5..4ebf17f 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -79,7 +79,7 @@
   foreach t : gtests
     test(
       t,
-      files('run_with_tmp.sh'),
+      run_with_tmp,
       env: {'TMPTMPL': 'stdplus-test.XXXXXXXXXX'},
       args: executable(
         t.underscorify(), t + '.cpp',
diff --git a/test/run_with_tmp.sh b/test/run_with_tmp.sh
deleted file mode 100755
index 485d6a3..0000000
--- a/test/run_with_tmp.sh
+++ /dev/null
@@ -1,6 +0,0 @@
-#!/bin/bash
-TMPDIR="$(mktemp -d --tmpdir "${TMPTMPL-tmp.XXXXXXXXXX}")" || exit
-trap 'rm -rf -- "$TMPDIR"' EXIT
-export TMPDIR
-echo "Exec $* with TMPDIR=$TMPDIR" >&2
-"$@"