Add opentsdb to CI

Author: antonkomarev

.github/workflows/tests.yml

@@ -15,7 +15,7 @@ jobs:
           --health-cmd="curl -f http://opentsdb:4242/api/version"
           --health-interval=10s
           --health-timeout=10s
-          --health-retries=5
+          --health-retries=10
         env:
           TSDB_LOG_LEVEL: "DEBUG"