CPU and Max RSS Analysis tools

[ChrisPaulBennett]

This apart of 3 pull requests for adding CPU time and Max RSS analysis to the Cylc UI.

This adds the Max RSS and CPU time (as measured by cgroups) to the table view, box plot and time series views.

Linked to;
cylc/cylc-flow#6663
cylc/cylc-uiserver#675

Check List

• I have read CONTRIBUTING.md and added my name as a Code Contributor.
• Contains logically grouped changes (else tidy your branch by rebase).
• Does not contain off-topic changes (use other PRs for other changes).
• Applied any dependency changes to both setup.cfg (and conda-environment.yml if present).
• Tests are included (or explain why tests are not needed).
• Changelog entry included if this is a change that can affect users
• Cylc-Doc pull request opened if required at cylc/cylc-doc/pull/XXXX.
• If this is a bug fix, PR should be raised against the relevant ?.?.x branch.

[MetRonnie]

Btw it looks like you have accidentally pushed this branch both to your fork and this upstream repo. I'm deleting the branch on here but it will remain on your fork.