Fixed lint warning

Signed-off-by: Juraci Paixão Kröhling <juraci@kroehling.de>

processor/authenticationprocessor/oidc_authenticator.go

@@ -87,7 +87,7 @@ func (o *oidcAuthenticator) authenticate(ctx context.Context) (bool, error) {
 		}
 
 		claims := map[string]interface{}{}
-		if err := idToken.Claims(&claims); err != nil {
+		if err = idToken.Claims(&claims); err != nil {
 			// currently, this isn't a valid condition, the Verify call a few lines above
 			// will already attempt to parse the payload as a json and set it as the claims
 			// for the token. As we are using a map to hold the claims, there's no way to fail