Delete encrypted storage in a try catch to avoid errors.

[DavidKutu]

For #5934

• Pull request represents a single change (i.e. not fixing disparate/unrelated things in a single PR).
• Title summarizes what is changing.
• Has a news entry file (remember to thank yourself!).
• Appropriate comments and documentation strings in the code.
• Has sufficient logging.
• Has telemetry for enhancements.
• Unit tests & system/integration tests are added/updated.
• Test plan is updated as appropriate.
• package-lock.json has been regenerated by running npm install (if dependencies have changed).

[rchiodo]

I believe this won't be caught here. The promise is ignored.

You might try this instead:

this.extensionContext.secrets.delete(`${service}.${key}`).catch(traceError);

[DavidKutu]

thenables don't have .catch

[DavidKutu]

I'll put the await back

[rchiodo]

⏲️