Switch `CredentialsMatcher` implementations to be `record`s

[jglick]

As a follow-up to #1001, it would be nice to simplify Matcher implementations. For example IdMatcher could be reduced to just

public record IdMatcher(@NonNull String id) implements CredentialsMatcher {
    @Override
    public boolean matches(@NonNull Credentials item) {
        return item instanceof IdCredentials idc && id.equals(idc.getId());
    }
}

This would replace the advice in

credentials-plugin/src/main/java/com/cloudbees/plugins/credentials/CredentialsMatcher.java

Lines 32 to 34 in 36c1cee

	* <li>Implement {@link Object#toString()}</li>
	* <li>Implement {@link Object#equals(Object)} and {@link Object#hashCode()}</li>
	* <li>Define a {@code serialVersionUID} field to ensure consistent serialization</li>

It is important to retain binary compatibility for the constructors, since many plugins appear to instantiate at least IdCredentials directly rather than going through CredentialsMatchers.withId.

[shubh586]

I’ve opened a PR simplifying matcher implementations using Java records (follow-up to #1001).
This removes the need for custom equals/hashCode/toString and serialVersionUID in record-based matchers.
PR: #1009