git: openjdk/jfx-sandbox: glass_gtk_bug_squashing: Improve testing

[duke]

Changeset: d90b2a54
Branch: glass_gtk_bug_squashing
Author:    Thiago Milczarek Sayao <thiago.sayao at gmail.com>
Date:      2025-04-08 09:32:11 +0000
URL:       https://git.openjdk.org/jfx-sandbox/commit/d90b2a5496e07f5b6c76719945e5890b73d06b6f

Improve testing

+ tests/system/src/test/java/test/javafx/stage/StageProgamaticallyChangeSizeWhileUnresizableTest.java
- tests/system/src/test/java/test/javafx/stage/StagePropertiesRetentionTest.java
- tests/system/src/test/java/test/javafx/stage/StagePropertyMixTest.java
+ tests/system/src/test/java/test/javafx/stage/StageShouldNotChangePropertiesWhileNotFloatingTest.java
! tests/system/src/test/java/test/javafx/stage/StageTestBase.java