Fix rerunning the tests in case of LeakSanitizer crash

The changes of 211cde11d4 (Rerun the test if LeakSanitizer crashed while
running it, 2021-02-05) didn't work because the script is executed with
"-e" shell option and so none of the commands added there was actually
run.

Fix this by using the usual "|| rc=$?" construct instead.

.github/workflows/ci.yml

@@ -199,18 +199,16 @@ jobs:
         working-directory: tests
         run: |
           # Explicitly use bash because /bin/sh doesn't have pipefail option
-          /bin/bash -o pipefail -c './test 2>&1 | tee test.out'
-          rc=$?
+          /bin/bash -o pipefail -c './test 2>&1 | tee test.out' || rc=$?
           if [ ${{ matrix.use_asan }} ]; then
             # Work around spurious crashes by running the test again.
             # See https://github.com/google/sanitizers/issues/1353
             if fgrep -q 'LeakSanitizer has encountered a fatal error' test.out; then
                 echo '+++ Rerunning the tests once again after LeakSanitizer crash +++'
-                ./test
-                rc=$?
+                ./test || rc=$?
             fi
           fi
-          if [ "$rc" != 0 ]; then
+          if [ -n "$rc" ]; then
             echo '*** Tests failed, contents of httpbin.log follows: ***'
             echo '-----------------------------------------------------------'
             cat httpbin.log