[Routing] trigger deprecation warning for deprecated features that will be removed in 2.3
adjusted tests to not use RouteCollection::getPrefix
adjust tests to no use addPrefix with options
refactor interator test that was still assuming a tree
added tests for remove() that wasnt covered yet and special route name
adjust RouteCollectionTest for the addCollection change and refactor the tests to only skip the part that really needs the config component
added tests for addDefaults, addRequirements, addOptions
add test for uniqueness of resources
adjust routing tests to not use prefix in addCollection
remove() should not use deprecated getParent() so it does not trigger deprecation internally
merged branch Tobion/deprecation-trigger (PR #7266)

This PR was merged into the 2.2 branch.

Commits
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c0687cd remove() should not use deprecated getParent() so it does not trigger deprecation internally
708c0d3 adjust routing tests to not use prefix in addCollection
6180c5b add test for uniqueness of resources
c0de07b added tests for addDefaults, addRequirements, addOptions
0a1cfcd adjust RouteCollectionTest for the addCollection change and refactor the tests to only skip the part that really needs the config component
ea694e4 added tests for remove() that wasnt covered yet and special route name
9e2bcb5 refactor interator test that was still assuming a tree
ceb9ab4 adjust tests to no use addPrefix with options
2b8bf6b adjusted tests to not use RouteCollection::getPrefix
acff735 [Routing] trigger deprecation warning for deprecated features that will be removed in 2.3

Discussion
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[2.2][Routing] Trigger deprecation and refactor tests to not use deprecated methods

| Q             | A
| ------------- | ---
| Bug fix?      | [yes]
| New feature?  | [no]
| BC breaks?    | [no]
| Deprecations? | [no]
| Tests pass?   | [yes]
| License       | MIT

@fabpot please don't squash because it also added new tests