Improve speed of readiness detection for Windows instances

[jakauppila]

Move the fetching of the Windows admin password into the wait_until_ready function to speed up readiness detection of Windows instances

Description

In instances where the administrative username/password is not defined by the user, if we change the Windows instance readiness detection to use the retrieval of the admin password as a readiness factor rather than the console output, we can speed up the readiness detection for Windows instances by 4+ minutes.

In my testing:

• with a c6i.large, the instance took ~60 seconds to become "ready" (~20 seconds to become "running" and ~40 seconds to retrieve the password)
• with a t3a.nano, the instance took ~80 seconds to become "ready" (~10 seconds to become "running" and ~70 seconds to retrieve the password)

In contrast to the existing logic:

• with a c6i.large, the instance took ~310 seconds to become "ready"
• with a t3a.nano, the instance took ~350 seconds to become "ready"

Issues Resolved

#575

Check List

• All tests pass. See TESTING.md for details.
• New functionality includes testing.
• New functionality has been documented in the README if applicable.

[jakauppila]

This should be good to go now!

@damacus Looks like there's an issue with the yamllint action: actionshub/yamllint#8