[migractions] Better handle removal of RQLConstraint in sync_schema
In rdef synchronisation, filter unmodified constraints before processing the
sets of old and new constraints.
Add a new `constraint_by_eid` method on RelationDefinitionSchema, which
eliminates the ambiguity of `constraint_by_type` usage when several
constraints of the same type are involved in the same migration.
Closes #3633644.
CSS Coding Standards
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(Draft, to be continued)
:Naming: camelCase
Indentation rules
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- 2 espaces avant les propriétés
- pas d'espace avant les ":", un espace après
- 1 seul espace entre les différentes valeurs pour une même propriété
Documentation
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Please keep rules semantically linked grouped together, with a comment about
what they are for.
Recommendation
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- Try to use existing classes rather than introduce new ones
- Keep things as simple as possible while in the framework
- Think about later customization by application
- Avoid introducing a new CSS file for a few lines of CSS, at least while the
framework doesn't include packing functionalities