Add a status code to the IdentityProviderException

Previously this exception would always have `0` as the status code,
making it impossible to know what was the status of the response that
caused that exception.

Add an assertion to test where one was missing

This change adds an assertion to
testCanDecryptResponseReturnsResponseWhenEncryptionIsUsed to complete
the test and avoid it being risky; ensuring that it does something
meaningful.

Fix requiring multiple different versions of PHP and firebase/php-jwt

Version support and specific settings for 18 and 20 keycloak version

Fix errors without a description

Merge pull request stevenmaguire#52 from panigrc/fix/oauth2-client-ve…

…rsion

Allow league/oauth2-client ^2.0

Merge pull request stevenmaguire#21 from KonstantinCodes/master

Allow firebase/php-jwt 5.0

Merge pull request stevenmaguire#17 from colq2/fix-update-error

Fix update error

Merge pull request stevenmaguire#31 from jgdevweb/change-default-scope

change default scope name to profile for Keycloak V11