ServerBearerTokenAuthenticationConverter throws exceptions instead of signalling error

[qavid]

Describe the bug
ServerBearerTokenAuthenticationConverter throws exceptions in case
bearer token doesn't match pattern
or
authorization header and access token query param are both present in request.

To Reproduce
Send invalid bearer token in authorization header. For example, you can add test bellow to ServerBearerTokenAuthenticationConverterTests.

@Test
public void simpleTest() {
	MockServerHttpRequest.BaseBuilder<?> request = MockServerHttpRequest
			.get("/")
			.header(HttpHeaders.AUTHORIZATION, "bearer !!");

	assertThatCode(() -> this.converter.convert(MockServerWebExchange.from(request))).doesNotThrowAnyException();
}

Expected behavior
ServerBearerTokenAuthenticationConverter should signal error after subscribing to returned publisher not to throw error after calling convert method.

I'm able to submit a PR.

[rwinch]

Thank you for reporting this and volunteering to submit a PR @qavid! We'd love to see a pull request for this issue.

[qavid]

Hi @rwinch , I'll work on it next week/weekend after my vacation.