Increase ulimit for CI testing (#19409)

The CI fails because of ulimit issues.

Ticket: https://mattermost.atlassian.net/browse/DOPS-783

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

.circleci/config.yml

@@ -323,7 +323,6 @@ jobs:
       - run:
           name: Run Tests
           command: |
-            ulimit -n 8096
             mkdir -p mattermost-server/client/plugins
             cd mattermost-server/build
             docker run -it --net circleci_mm-test \
@@ -385,7 +384,6 @@ jobs:
           name: Postgres schema migration validation
           command: |
             cd mattermost-server/build
-            ulimit -n 8096
             mkdir -p mattermost-server/client/plugins
             echo "Creating databases"
             docker-compose --no-ansi exec -T postgres sh -c 'exec echo "CREATE DATABASE migrated; CREATE DATABASE latest;" | exec psql -U mmuser mattermost_test'
@@ -414,7 +412,6 @@ jobs:
           name: MySQL schema migration validation
           command: |
             cd mattermost-server/build
-            ulimit -n 8096
             mkdir -p mattermost-server/client/plugins
             echo "Creating databases"
             docker-compose --no-ansi exec -T mysql mysql -uroot -pmostest -e "CREATE DATABASE migrated; CREATE DATABASE latest; GRANT ALL PRIVILEGES ON migrated.* TO mmuser; GRANT ALL PRIVILEGES ON latest.* TO mmuser"