PMM-15406 Feature build

[nachodd]

Feature build for percona/pmm branch PMM-15406-test-servicenow-connection — [FE] Test the ServiceNow delivery connection and normalize the stored endpoint.

The branch is stacked: it carries PMM-15205-sep-fb and PMM-15419 beneath it, so this image contains the whole ServiceNow connection tab, not only the test action.

PMM PR: percona/pmm#5892

[JNKPercona]

Server docker: perconalab/pmm-server-fb:PR-4560-ebcb7c3
Client docker: perconalab/pmm-client-fb:PR-4560-ebcb7c3
Client tarball: https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4560-ebcb7c3.tar.gz
Staging instance: https://pmm.cd.percona.com/job/pmm3-aws-staging-start/parambuild/?DOCKER_VERSION=perconalab/pmm-server-fb:PR-4560-ebcb7c3&CLIENT_VERSION=https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4560-ebcb7c3.tar.gz

[JNKPercona]

API tests have succeded: https://pmm.cd.percona.com/job/pmm3-api-tests/7272/

[JNKPercona]

Server docker: perconalab/pmm-server-fb:PR-4560-8b19fd5
Client docker: perconalab/pmm-client-fb:PR-4560-8b19fd5
Client tarball: https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4560-8b19fd5.tar.gz
Staging instance: https://pmm.cd.percona.com/job/pmm3-aws-staging-start/parambuild/?DOCKER_VERSION=perconalab/pmm-server-fb:PR-4560-8b19fd5&CLIENT_VERSION=https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4560-8b19fd5.tar.gz

[JNKPercona]

API tests have succeded: https://pmm.cd.percona.com/job/pmm3-api-tests/7319/