Using the SecurityMockServerConfigurers.java requires the com.nimbusds oauth2-oidc-sdk on the classpath #9923
Description
Describe the bug
When using the SecurityMockServerConfigurer e.g. to test with an opaque OAuth2 token tests fail due to an NoClassDefFoundError. The root of the error is that in the SecurityMockServerConfigurer the `StringUtils from the com.nimbusds oauth2-oidc-sdk are used. This is an optional dependency of spring-security and in our case, where we're not dealing with oidc, not on the classpath.
Currently the Workaround is to add the sdk to the dependencies, but that should not be necessary.
To Reproduce
Use SecurityMockServerConfigurer#mockOpaqueToken in a project that has no dependency to the oauth2-oidc-sdk.
Expected behavior
Dependency should not be mandatory for unrelated functionality.