Allows rails 7 with minor versions

[aYaremchuk]

Rails 7.1.3 incompatible

Could not find compatible versions

Because every version of crypt_keeper depends on activerecord >= 7.0.0, < 7.1.A
  and rails >= 7.1.3 depends on activerecord = 7.1.3,
  every version of crypt_keeper is incompatible with rails >= 7.1.3.
So, because Gemfile depends on rails = 7.1.3
  and Gemfile depends on crypt_keeper >= 0,
  version solving has failed.

Added minor change to support minor versions of rails 7
Also changed path version of gem

[jmazzi]

@aYaremchuk the tests are failing

[jmazzi]

@Capncavedan @aYaremchuk tests are still failing as of today; please consider investigating this if you would like to see a gem cut for this version.

[johan-smits]

@jmazzi looking at the changes it would suspect to fail only for the 7.1 rails versions. But all tests fail also the previous ones. Could it be that also the main branch fails recently?

[aYaremchuk]

There is an issue with public/private keys.
These keys do not have an expiration date, but tests fail even with minor changes.

It appears this issue was resolved in the following pull request: 203.

[aYaremchuk]

Closing this PR.

It seems the issue with the broken tests was resolved in this pull request: link.