MAINT: rename SetFieldStrategy to SerializeFieldStrategy

src/main/java/org/caosdb/server/entity/Entity.java

src/main/java/org/caosdb/server/entity/EntityInterface.java

...main/java/org/caosdb/server/entity/TransactionEntity.java

...a/org/caosdb/server/entity/container/ParentContainer.java

...org/caosdb/server/entity/container/PropertyContainer.java

.../java/org/caosdb/server/entity/wrapper/EntityWrapper.java

...org/caosdb/server/entity/xml/DomainToElementStrategy.java

...org/caosdb/server/entity/xml/EntityToElementStrategy.java

...a/org/caosdb/server/entity/xml/FileToElementStrategy.java

...db/server/entity/xml/IdAndServerMessagesOnlyStrategy.java

...org/caosdb/server/entity/xml/ParentToElementStrategy.java

...g/caosdb/server/entity/xml/PropertyToElementStrategy.java

.../org/caosdb/server/entity/xml/SerializeFieldStrategy.java

.../java/org/caosdb/server/entity/xml/ToElementStrategy.java

...n/java/org/caosdb/server/grpc/CaosDBToGrpcConverters.java

src/test/java/org/caosdb/server/entity/SelectionTest.java

...caosdb/server/entity/container/PropertyContainerTest.java

...osdb/server/entity/xml/PropertyToElementStrategyTest.java