Fix vectorized tracking for `TransverseDeflectingCavity`

Description

Adds some missing dimensional expansions in the TransverseDeflectingCavity code to fix a bug with some vectorisation setups.

Fixes #270.

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[x] Bug fix (non-breaking change which fixes an issue)
[ ] New feature (non-breaking change which adds functionality)
[ ] Breaking change (fix or feature that would cause existing functionality to change)
[ ] Documentation (update in the documentation)

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