Create new public cloud techdocs section called "Project set management and access"

**Describe the Issue**
As our tech docs grow we want to make sure that the menu is still readable and intuitive to new users. Abi, Pilar and I met and had a discussion about the two new techdoc pages about user management and cost management dashboards. We decided that they warrant a new section and decided to call it "Project set management and access".

**Additional Context**
https://developer.gov.bc.ca/docs/default/component/public-cloud-techdocs

**Acceptance Criteria**
- [ ] Create a new menu section called "Project set management and access"
- [ ] Add the "AWS user management" document to it
- [ ] Add the "AWS billing and cost management dashboards" document to it
- [ ] Ensure that all page titles and menu items have the same names

Start with the linked public cloud techdocs site and inspect the current menu alongside the “AWS user management” and “AWS billing and cost management dashboards” documents. Create the named section, place both documents in it, and verify that page titles and menu items match exactly.

Written by the indexing model from the issue text.