[BUG] Remove slow validation check during module search (CPS-2190 #2)

[BUG] Remove slow validation check during module search (CPS-2190 #2)

The check for existing modules is extremely slow, being dependent on
the file sizes of the Yang modules being queries.
The validation check is also completely unnecessary, since it simply
ignores any exceptions and returns an empty set, which the main logic
does implicitly. (The Dataspace check is also not needed, as the NCMP
dataspace is guaranteed to exist.)

Issue-ID: CPS-2190
Signed-off-by: danielhanrahan <daniel.hanrahan@est.tech>
Change-Id: I329c1f8aac3f50bda0333e6c9c686f47af2e009f