Add absolute path support to other CLI commands

[tomasreimers]

Following up on #6660 and adding absolute path support to the other CLI commands (sorry it took me so long!)

This is the same change + the type change necessary to prevent a breakage (someone please correct me if I'm missing anything)!

Thanks!

[imnotjames]

Until we can confirm that adding path.resolve won't break anything I think this looks good to me.

[imnotjames]

Oh no! This broke the build.

https://app.circleci.com/pipelines/github/typeorm/typeorm/1536/workflows/83ce2f7e-0904-4b1f-a39e-7dd6e7a9f1a6/jobs/3259

src/commands/EntityCreateCommand.ts:50:21 - error TS2322: Type 'string | undefined' is not assignable to type 'string'.
  Type 'undefined' is not assignable to type 'string'.

50                     directory = connectionOptions.cli ? connectionOptions.cli.entitiesDir : undefined;
                       ~~~~~~~~~

src/commands/SubscriberCreateCommand.ts:51:21 - error TS2322: Type 'string | undefined' is not assignable to type 'string'.
  Type 'undefined' is not assignable to type 'string'.

51                     directory = connectionOptions.cli ? connectionOptions.cli.subscribersDir : undefined;
                       ~~~~~~~~~


Found 2 errors.