cirrus ci: Check race condition

with gmake -j 1 distcheck

Signed-off-by: Juergen Repp <juergen_repp@web.de>

.cirrus.yml

@@ -30,4 +30,4 @@ task:
   script:
     ./bootstrap &&
     ./configure --enable-self-generated-certificate --enable-unit=yes --enable-integration=yes --with-crypto=ossl --disable-doxygen-doc --enable-tcti-swtpm=no --enable-tcti-libtpms=no --enable-tcti-mssim=yes --disable-dependency-tracking &&
-    gmake -j distcheck || { cat /tmp/cirrus-ci-build/tpm2-tss-*/_build/sub/test-suite.log; exit 1; }
+    gmake -j 1 distcheck || { cat /tmp/cirrus-ci-build/tpm2-tss-*/_build/sub/test-suite.log; exit 1; }