feat: configure fixedOrder globally instead for every spawner

[kschrab]

Description

• Instead of configuring fixedOrder for every vehicles spawner, it can now be configured once in the common configuration section of the mapping_config.json
• This also allows to consider this config when transforming ScenarioVehicleRegistration to VehicleRegistration

Issue(s) related to this PR

• Resolves internal issue 678

Affected parts of the online documentation

Changes in the documentation required?

Yes, separate MR is created.

Definition of Done

Prerequisites

• You have read CONTRIBUTING.md carefully.
• You have signed the Contributor License Agreement.
• Your GitHub user id is linked with your Eclipse Account.

Required

• The title of this merge request follows the scheme type(scope): description (in the style of Conventional Commits)
• You have assigned a suitable label to this pull request (e.g., enhancement, or bugfix)
• origin/main has been merged into your Fork.
• Coding guidelines have been followed (see CONTRIBUTING.md).
• All checks on GitHub pass.
• All tests on Jenkins pass.

Requested (can be enforced by maintainers)

• New functionality is covered by unit tests or integration tests. Code coverage must not decrease.
• If a bug has been fixed, a new unit test has been written (beforehand) to prove misbehavior
• There are no new SpotBugs warnings.

Special notes to reviewer

[kschrab]

@rprotzmann all tests are green again, needed to set fixedOrder = true for some test scenarios as this affected how vehicles were expected to be mapped for the test asserts. feel free to merge