Remove bash-ism.

Index: tests/testrun.sh
--- tests/testrun.sh.orig
+++ tests/testrun.sh
@@ -472,7 +472,7 @@ execEncTest() {
 rm -rf $tmpfile $tmpfile.2 tmpfile.3
 
 # run tests
-source "$testfile"
+. "$testfile"
 
 # print results
 echo "--- TOTAL OK: $count_success; TOTAL FAILED: $count_fail; TOTAL SKIPPED: $count_skip" >> $logfile