github-ci: do distcheck on fedora 31 build

There were no distchecks being done on builds from git.

.github/workflows/builds.yml

@@ -249,6 +249,7 @@ jobs:
       - run: ./configure --enable-unittests
       - run: make -j2
       - run: make check
+      - run: make distcheck
       - name: Fetching suricata-verify
         run: git clone https://github.com/OISF/suricata-verify.git
       - name: Running suricata-verify