PMM-14915 Remove UI events.

[JiriCtvrtka]

https://jira.percona.com/browse/PMM-14915

PMM PR: percona/pmm#5422

[JNKPercona]

Server docker: perconalab/pmm-server-fb:PR-4376-474db50
Client docker: perconalab/pmm-client-fb:PR-4376-474db50
Watchtower docker: perconalab/pmm-watchtower-fb:PR-4376-474db50
Client tarball: https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4376-474db50.tar.gz
Staging instance: https://pmm.cd.percona.com/job/pmm3-aws-staging-start/parambuild/?DOCKER_VERSION=perconalab/pmm-server-fb:PR-4376-474db50&CLIENT_VERSION=https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4376-474db50.tar.gz

[JNKPercona]

API tests have failed: https://pmm.cd.percona.com/job/pmm3-api-tests/6255/

[JNKPercona]

Server docker: perconalab/pmm-server-fb:PR-4376-5659e25
Client docker: perconalab/pmm-client-fb:PR-4376-5659e25
Watchtower docker: perconalab/pmm-watchtower-fb:PR-4376-5659e25
Client tarball: https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4376-5659e25.tar.gz
Staging instance: https://pmm.cd.percona.com/job/pmm3-aws-staging-start/parambuild/?DOCKER_VERSION=perconalab/pmm-server-fb:PR-4376-5659e25&CLIENT_VERSION=https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4376-5659e25.tar.gz

[JNKPercona]

API tests have failed: https://pmm.cd.percona.com/job/pmm3-api-tests/6262/