[ECO-4874] Replaced all occurences of checking error message

[maratal]

Replaced all occurences of checking error message instead of error code (or removed where the error code check was already presented) except places where error is locally generated (since it doesn't contain proper error code - 0 usually).

Closes #1946

[lawrence-forooghian]

To check I’ve understood — the error messages that you've removed the checks for are all ones that are generated by the server?

[maratal]

To check I’ve understood — the error messages that you've removed the checks for are all ones that are generated by the server?

correct

[owenpearson]

Hey @maratal, I just ran into an issue with ably-cocoa tests checking against realtime error messages and the assertion which failed was this one

ably-cocoa/Test/Tests/RealtimeClientTests.swift

Line 747 in 938ee76

expect(error.localizedDescription).to(contain("Invalid accessToken"))

, would you mind fixing that in this PR too?

[owenpearson]

@maratal found some more here as well:

• ably-cocoa/Test/Tests/AuthTests.swift

  Line 4090 in 938ee76

  expect(reason.description).to(satisfyAnyOf(contain("invalid signature"), contain("signature verification failed")))

• ably-cocoa/Test/Tests/AuthTests.swift

  Line 4141 in 938ee76

  expect(reason.description).to(satisfyAnyOf(contain("invalid signature"), contain("signature verification failed")))

• ably-cocoa/Test/Tests/AuthTests.swift

  Line 4261 in 938ee76

  expect(reason.description).to(satisfyAnyOf(contain("invalid signature"), contain("signature verification failed")))

• ably-cocoa/Test/Tests/AuthTests.swift

  Line 4338 in 938ee76

  expect(error?.message).to(contain("permission denied"))

• ably-cocoa/Test/Tests/RealtimeClientConnectionTests.swift

  Line 2099 in 938ee76

  expect(reason.message).to(contain("Key/token status changed (expire)"))

[maratal]

Thanks @owenpearson I was looking for error.message but there are also description, localizedDescription, reason.message and error?.message! 🤦‍♂️

[owenpearson]

Looks great, thanks!