tests: Skip test cases for message parts

Message parts are not yet supported with SQLite.

See 91ab2f8 (Implement early basic sqlite database code) and
c484c81 (Remove tracker database and sparql query code).
tests: Skip test cases for contact matching

Contact matching is not yet supported with SQLite.

See c484c81 (Remove tracker database and sparql query code).
ut_eventmodel: Fix clean-up

Clean-up of events is broken since commit e7bde7e (Add
RecentContactsModel) which introduced addedEventIds to cleanup only
events added via addTestEvent interface. Only minority of test events in
ut_eventmodel is created via this interface. Most of them are only
cleaned up because they are assigned a groupId (compare
cleanupTestGroups() with cleanupTestEvents from common.cpp).  'call'
event is not set a groupId and so it is not cleaned-up upon exit.
Deleting 'call' event "manually" in EventModelTest::cleanupTestCase() as
a QUICK FIX!
ut_callmodel: Use 'sips' URI scheme inst. of 'sip'

This is necessary since 18d6d14 (Use generic phone number functions) as
QtContactsSqliteExtensions::normalizePhoneNumber() only recognizes the
"secure" SIP URIs and (as confirmed by qtcontacts-sqlite developer) this
is not likely to change.
ut_callmodel: Fix testDeleteEvent

Broken since 4d16bd8 (Fix CallModel eventDeleted signal with groups).
The first occurence might be a typo from 5f16ec7 (Fix unit tests for
sqlite backend) as well.
tests: Skip test cases for query limit

Query limit is not yet supported with SQLite.

See 91ab2f8 (Implement early basic sqlite database code).
ut_callmodel: Fix testModifyEvent

Broken since e15d6c4 (Fix CallModel insertion in grouped mode).
tests: Fix cleanupTestEvents()

Note that this bug is with no impact on test results at the time of fixing.