fix(py3): Make event ingestion test more robust (#693)

We were relying on the public DSN field coming first from the API and with Python 3, that's not the case to the tests were failing. This PR makes DSN extraction a bit more robust while still avoiding a full-fledged JSON parser.

Author: BYK

test.sh

@@ -74,7 +74,7 @@ done
 # Set up initial/required settings (InstallWizard request)
 sentry_api_request "internal/options/?query=is:required" -X PUT --data '{"mail.use-tls":false,"mail.username":"","mail.port":25,"system.admin-email":"[email protected]","mail.password":"","mail.from":"root@localhost","system.url-prefix":"'"$SENTRY_TEST_HOST"'","auth.allow-registration":false,"beacon.anonymous":true}' > /dev/null
 
-SENTRY_DSN=$(sentry_api_request "projects/sentry/internal/keys/" | awk 'BEGIN { RS=",|:{\n"; FS="\""; } $2 == "public" { print $4; exit; }')
+SENTRY_DSN=$(sentry_api_request "projects/sentry/internal/keys/" | awk 'BEGIN { RS=",|:{\n"; FS="\""; } $2 == "public" && $4 ~ "^http" { print $4; exit; }')
 # We ignore the protocol and the host as we already know those
 DSN_PIECES=(`echo $SENTRY_DSN | sed -ne 's|^https\?://\([0-9a-z]\+\)@[^/]\+/\([0-9]\+\)$|\1\n\2|p'`)
 SENTRY_KEY=${DSN_PIECES[0]}