Remove the nested styling from tbxforms components

[helenb]

This means that when styles for tbxforms components are being updated in projects, we don't have nested styling to override. See #40

Note that due to not currently having a local set-up where I can test this, this will need testing as well as code-reviewing.

[helenb]

I see that the test_python CI process has failed, but just to clarify this should be unrelated to my changes, which are only to CSS

[jams2]

Looks like we need to bump the poetry version (python-poetry/poetry#7878)

[helenb]

@kbayliss I see there's some activity happening on tbxforms at the moment. I don't have a local build any more (it was on my old laptop) - if you have a sec could you rebase and test this branch? It failed tests due to the poetry version but that must be fixed now if other branches are passing. thanks!

[kbayliss]

@helenb yep! I'll make sure it gets added to the release

[helenb]

@helenb yep! I'll make sure it gets added to the release

Thank you!

[kbayliss]

This work has been merged as part of #52 (it was easier to do within an integration branch due to so many related changes)