[server] Fixed issue with the adapters cache of a cloned EditedEntity The adapters' cache of the entity within an EditedEntity used to be copied along the entity itself during a cloning operation of the EditedEntity. This raises an issue when the adapters' cache is not empty and contains cached values linking to transaction-specific data (or the transaction itself). This prevents the clone EditedEntity being used in a transaction outside the one that created it. This change resets the adapters' cache of the new copy so that no cached value remain. The new copy can then be used in a new transaction afterwards.

### Requirements for tests in various cubicweb/**/test directories. ###

## shared by several test folders
cubicweb-card == 0.5.8
docutils
Twisted < 16.0.0
webtest

## cubicweb/test
Pygments
mock
#fyzz XXX pip install fails
cubicweb-file == 1.18.0
cubicweb-localperms == 0.3.2
cubicweb-tag == 1.8.3

## cubicweb/devtools/test
flake8

## cubicweb/hooks/test
psycopg2

## cubicweb/pyramid/test
pyramid >= 1.5.0
waitress >= 0.8.9
wsgicors >= 0.3
pyramid_multiauth

## cubicweb/sobject/test
cubicweb-comment == 1.12.2