Container: Investigate Flaky/Regressed Tests

[cdietrich]

• Bug486584Test https://github.com/eclipse/xtext-eclipse/issues/606
• ResourceDescriptionUpdaterTest https://github.com/eclipse/xtext-eclipse/issues/796
• RequestManagerTest https://github.com/eclipse/xtext-core/issues/622
• SWTBot Tests https://github.com/eclipse/xtext/issues/2277
• SimpleProjectsIntegrationTest IntegrationTest https://github.com/eclipse/xtext/issues/2410

[cdietrich]

moved to 2.17 since we dont find the time for investigation

[cdietrich]

move to 2.22

[cdietrich]

move to 2.24