[datafeed] attempt to acquire synchronization lock even when force is given instead of the implementation in e717da3dc164, raise an error if the lock is already grabbed and catch this error in the caller. See discussion on https://www.cubicweb.org/revision/10790765 Closes #10451635

[schema] Cache RQL expressions on schema loading Add a mapping rql string to rql statement Deserializing schema is ~36% faster with a lot (> 4000) expressions like those generated by cubicweb-container.

[schema] Avoid parsing RQL expressions twice on schema loading Kill full_rql (unnecessary) Use snippet_rql rather than rqlst when possible Don't access to rqlst cachedproperty from __init__ Deserializing schema is ~40% faster with a lot (> 4000) expressions like those generated by cubicweb-container.