GDK dashboard: Filter events by APP ID

This filter will come handy once we've switched to the new ClickHouse instance which contain events from Production and CI.

How I wanted to verify as snapshot

$ ./test-dashboard.sh development-tooling/gdk.dashboard.jsonnet
Installed https://dashboards.gitlab.net/dashboard/snapshot/kjPOB7jZ0cfVusMN9fNM0hwKZeNuSHqN?var-environment=gprd&orgId=1&var-PROMETHEUS_DS=mimir-gitlab-gprd&var-stage=main - development-tooling: GDK

But I got Datasource GitLab Development Kit ClickHouse was not found error:

How I verified this locally

following steps from https://gitlab.com/gitlab-org/quality/engineering-productivity/team/-/issues/598#note_2730460997

1. Setup grafana via docker
2. Setup and start ClickHouse locally via GDK
3. Setup a ClickHouse datasource in Grafana to match remote's datasource name GitLab Development Kit ClickHouse
4. Import data from old PA instance to local ClickHouse instance
5. Point to new ClickHouse database and table sed -i 's/gitlab_project_74823.snowplow_events/default.events/g' $(rg -l gitlab_project development-tooling/)
6. ./test-dashboard.sh -D development-tooling/gdk.dashboard.jsonnet | jq | pbcopy
7. Create a new Dashboard and paste the clipboard into JSON model
8. Save
9. Enjoy the App Id filter

Contributes to https://gitlab.com/gitlab-org/quality/engineering-productivity/team/-/issues/598.