Entity UIs - display API version in Info button

The Entity UIs display an Info button ("i") in their footer, that displays the UI's versions in a tooltip. This is very handy to confirm what UI build is being run (eg, for confirming its content).

We should add the API version being used to this Info tooltip.

**To do:**
- figure out how to get the API version (may be an environment variable, or a hash, or v1/v2)
- add API version to the About Text passed to the footer common component

**UIs to update:**
- [ ] Filings UI
- [ ] Create UI
- [ ] Edit UI
- [ ] Namerequest UI (if API version is available)