Increase the Gitlab Build timeout (#7604)

## Summary of changes

We are getting recently many errors from the Gitlab build job due to
timeouts. The job just does not finish it's task on time. While we
investigate ways to speed this process up, we should protect our CI by
increasing the timeout.

## Reason for change

## Implementation details

## Test coverage

## Other details
<!-- Fixes #{issue} -->


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Author: NachoEchevarria

.gitlab-ci.yml

@@ -20,6 +20,7 @@ build:
       - $DEPLOY_TO_REL_ENV == "true"
       - $CI_COMMIT_TAG # We don't need to build/publish when building a release tag
   stage: build
+  timeout: 2h
   tags: ["windows-v2:2019"]
   hooks:
     pre_get_sources_script: