PMM-14748: fix timezone shifting

[fabio-silva]

PMM-14748

[JNKPercona]

Server docker: perconalab/pmm-server-fb:PR-4333-9c5154f
Client docker: perconalab/pmm-client-fb:PR-4333-9c5154f
Watchtower docker: perconalab/pmm-watchtower-fb:PR-4333-9c5154f
Client tarball: https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4333-9c5154f.tar.gz
Staging instance: https://pmm.cd.percona.com/job/pmm3-aws-staging-start/parambuild/?DOCKER_VERSION=perconalab/pmm-server-fb:PR-4333-9c5154f&CLIENT_VERSION=https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4333-9c5154f.tar.gz

[JNKPercona]

API tests have succeded: https://pmm.cd.percona.com/job/pmm3-api-tests/5977/

[JNKPercona]

Server docker: perconalab/pmm-server-fb:PR-4333-0b9c44a
Client docker: perconalab/pmm-client-fb:PR-4333-0b9c44a
Watchtower docker: perconalab/pmm-watchtower-fb:PR-4333-0b9c44a
Client tarball: https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4333-0b9c44a.tar.gz
Staging instance: https://pmm.cd.percona.com/job/pmm3-aws-staging-start/parambuild/?DOCKER_VERSION=perconalab/pmm-server-fb:PR-4333-0b9c44a&CLIENT_VERSION=https://s3.us-east-2.amazonaws.com/pmm-build-cache/PR-BUILDS/pmm-client/pmm-client-PR-4333-0b9c44a.tar.gz

[JNKPercona]

API tests have failed: https://pmm.cd.percona.com/job/pmm3-api-tests/6066/