Improve stability of Gmail live tests

[martgil]

@martgil live tests probably fail because of current 45 minutes execution limit -

flowcrypt-browser/.semaphore/semaphore.yml

Line 64 in cbc1687

minutes: 45

Let's increase it to 60 minutes for now, but later will try to merge some live tests, so they'll be executed faster.

Originally posted by @sosnovsky in #5909 (comment)

[sosnovsky]

Some live Gmail tests are failing randomly (for example, multiple runs in https://flowcrypt.semaphoreci.com/branches/2c663124-ae1c-4a41-aef4-26c7100e51cd), so we temporarily disabled them.

Need to re-enable these tests and make them more stable.

Also with recently added tests, total time for running live tests is around 1 hour.
To reduce execution time let's merge some simple tests (for example, mail.google.com - rendering attachments + mail.google.com - simple attachments triggering processAttachments() keep "download all" button visible + mail.google.com - attachments which contain emoji in filename are rendered correctly can be merged into one mail.google.com - attachments rendered correctly)