Add LockClause for Dialect [DATAJDBC-498]

[spring-projects-issues]

MyeongHyeonLee opened DATAJDBC-498 and commented

The PESSIMISTIC LOCK syntax is required to resolve DATAJDBC-493  

However, the PESSIMISTC LOCK syntax(FOR UPDATE) is different in some DBMS engines.

So first add LockClause to Dialect. 

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Affects: 2.0 M3 (Neumann)

Referenced from: pull request #196

[spring-projects-issues]

Jens Schauder commented

Not exactly a duplicate, but resolved as part of DATAJDBC-493