build(deps): remove @aws/fully-qualified-names dependency

[justinmk3]

Problem

FQN not used since 6484c98. And it adds ~1 MB to the vsix size.

Solution

• Drop FQN dependency.
• Remove "temporary" hack added a long time ago for mynah: b2dc00a

---

• Treat all work as PUBLIC. Private feature/x branches will not be squash-merged at release time.
• Your code changes must meet the guidelines in CONTRIBUTING.md.
• License: I confirm that my contribution is made under the terms of the Apache 2.0 license.

[justinmk3]

/retrybuild