Fix secret revoke error with user_token

[alexhung]

Fix #237

Now secret lease revoke will check for empty access token from admin config and fall back to user_token config if it was empty.

Improve logging for TTL values.

Also fix errors when reading admin config if access_token is not set. Fixes #236

[Claudiordev]

Hi,

@alexhung

I builded this branch artifactory plugin and test it locally, still having an error on the leases being revoked as following:

2025-01-14T15:34:49.627+0100 [ERROR] expiration: failed to revoke lease: lease_id=artifactory/user_token/cfreita1/gom1W5LMI39gBib63zs0MscK error="failed to revoke entry: resp: &logical.Response{Secret:<nil>, Auth:<nil>, Data:map[string]interface {}{\"error\":\"admin access_token is not configured\"}, Redirect:\"\", Warnings:[]string(nil), WrapInfo:(*wrapping.ResponseWrapInfo)(nil), Headers:map[string][]string(nil), MountType:\"\"} err: %!w(<nil>)" attempts=2 next_attempt=20.774219754s

[alexhung]

@Claudiordev Thanks for testing/verifying. I've improved the path matching. This should work correctly now.