fix: APKAM keys expiry feature changes in at_commons, at_auth and at_onboarding_cli

[sitaram-kalluri]

- What I did

• Introduce auto expiry feature enables APKAM keys to expire after the specified duration.

- How I did it

• Changes in at_auth package

  • Introduce Duration apkamKeysExpiryDuration in "EnrollmentRequest" as an optional argument which represents the APKAM keys expiry duration, which accepts value from the user.

• Changes in at_commons package

  • Introduce apkamKeysExpiryDuration in enroll_verb_builder.dart. The expiry duration from the "enrollment_request" in at_auth package is set to the enroll_verb_builder.dart to propagate it to the at_secondary_server

• Changes in at_onboarding_cli

  • Introduce a new argument "-e" to enroll command to pass the expire duration to enroll, otp and spp verbs in human readable format.
  • In at_onboarding_service.dart, in sendEnrollRequest method, introduce apkamKeysExpiryDuration to set the expiry duration.

- How to verify it

• Manually tested the changes. From the on-boarding cli, send an enrollment request to secondary server with expiry duration set. Once the enrollment is approved, the APKAM keys can be used for authentication. After the duration, an exception stating keys are expired is returned when trying to authenticate.

• Test OTP with expiry duration:

~/IdeaProjects/atsign/core/at_libraries/packages/at_onboarding_cli/bin git:[2074-introducing-auto-expiry-and-time-to-birth-features-for-apkam-keys]
dart activate_cli.dart otp -a @sitaram -r vip.ve.atsign.zone -k /home/sitaram/.atsign/keys/@sitaram_key.atKeys -e 1m,10s
Connecting ... Connected
1PHZCZ

• Test SPP with expiry duration:

~/IdeaProjects/atsign/core/at_libraries/packages/at_onboarding_cli/bin git:[2074-introducing-auto-expiry-and-time-to-birth-features-for-apkam-keys]
dart activate_cli.dart spp -a @sitaram -r vip.ve.atsign.zone -k /home/sitaram/.atsign/keys/@sitaram_key.atKeys -s ABC123 -e 1m,10s
Connecting ... Connected
Server response: data:ok

• Test submit enrollment request:

~/IdeaProjects/atsign/core/at_libraries/packages/at_onboarding_cli/bin git:[2074-introducing-auto-expiry-and-time-to-birth-features-for-apkam-keys]
dart activate_cli.dart enroll -a @sitaram -r vip.ve.atsign.zone -s ABC123 -k /home/sitaram/.atsign/keys/@sitaram_test.atKeys -d my-device -n wavi:rw -p my-app3 -e 1d,10h,12m
Submitting enrollment request
Enrollment ID: fe56ac78-26b1-4ed7-aa6f-1370ee94f67a
Waiting for approval; will check every 10 seconds
Checking ...  not approved. Will retry in 10 seconds
Checking ...  approved.
Creating atKeys file
[Success] Your .atKeys file saved at /home/sitaram/.atsign/keys/@sitaram_test.atKeys

- Description for the changelog

• fix: APKAM keys expiry feature changes in at_commons, at_auth and at_onboarding_cli

NOTE: For easy of review, adding all the changes in this PR. Will move the changes to the respective packages before merging to trunk.

Pending work : Add functional tests in onboarding cli once the secondary server changes are merged.