Update @vardot/varbase-e2e to 2.0.7

Problem/Motivation

@vardot/varbase-e2e 2.0.7 turns the accessibility impact gate into a ladder: no serious accessibility violations now fails on critical as well. It also adds a one-step full check, element-scoped rule assertions, and probes that skip what assistive technology cannot reach.

This project is pinned to ^2.0.4, so none of that applies to its functional testing suite.

Proposed resolution

Bump @vardot/varbase-e2e to ^2.0.7 in package.json. One line, no test changes.

The gate is stricter on purpose, so the pipeline on the merge request is what proves the suite still passes.

Remaining tasks

✅ Update to 2.0.7
✅ Green pipeline
➖ Review
➖ Release

User interface changes

None. Test tooling only.

API changes

None.

Data model changes

None.