Missing support for urn:ietf:params:oauth:grant-type:jwt-bearer in ClientRegistrations

[ThomasKasene]

Describe the bug
It would appear ClientRegistrations.withProviderConfiguration does not yet support urn:ietf:params:oauth:grant-type:jwt-bearer:

if (grantTypes != null && !grantTypes.contains(GrantType.AUTHORIZATION_CODE)) {
	throw new IllegalArgumentException(
			"Only AuthorizationGrantType.AUTHORIZATION_CODE is supported. The issuer \"" + issuer
					+ "\" returned a configuration of " + grantTypes);
}

Related to gh-9780