feat: remove query escaping of base64 encoded credentials

Author: petexchai

internal/token.go

@@ -196,7 +196,9 @@ func newTokenRequest(tokenURL, clientID, clientSecret string, v url.Values, auth
 	}
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
 	if authStyle == AuthStyleInHeader {
-		req.SetBasicAuth(url.QueryEscape(clientID), url.QueryEscape(clientSecret))
+		// NOTE: This should be query-escaped, however the Aviva OAuth
+		// server does not accept query-escaped credentials.
+		req.SetBasicAuth(clientID, clientSecret)
 	}
 	return req, nil
 }

oauth2_test.go

@@ -74,7 +74,7 @@ func TestAuthCodeURL_Optional(t *testing.T) {
 
 func TestURLUnsafeClientConfig(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		if got, want := r.Header.Get("Authorization"), "Basic Q0xJRU5UX0lEJTNGJTNGOkNMSUVOVF9TRUNSRVQlM0YlM0Y="; got != want {
+		if got, want := r.Header.Get("Authorization"), "Basic Q0xJRU5UX0lEPz86Q0xJRU5UX1NFQ1JFVD8/"; got != want {
 			t.Errorf("Authorization header = %q; want %q", got, want)
 		}