Fix Test Configuration

- Typo in PlaceholderConfig was causing Windows builds to
resolve the CLASSPATH environment variable

Closes gh-9421

config/src/test/java/org/springframework/security/config/web/server/OAuth2ResourceServerSpecTests.java

@@ -615,7 +615,7 @@ public class OAuth2ResourceServerSpecTests {
 	@EnableWebFluxSecurity
 	static class PlaceholderConfig {
 
-		@Value("${classpath:org/springframework/security/config/web/server/OAuth2ResourceServerSpecTests-simple.pub}")
+		@Value("classpath:org/springframework/security/config/web/server/OAuth2ResourceServerSpecTests-simple.pub")
 		RSAPublicKey key;
 
 		@Bean