Enable strict_updatability_linting for NetworkStackApi30Shims

Fix the linter errors and enable strict_updatability_linting

Also use modules-utils method to check SDK version because
ShimUtils do not define the min_sdk and will be treated as
SDK 30 and conflict with the target SDK version(Q) if both
newInstance() and useApiAboveQ() are both defined as requires Q.
Thus, remove the reference for ShimUtils to align with other
usage and update corresponding usage accordingly.

Bug: 188851867
Test: m lint-check
Change-Id: Id6f7c2a4b919d76def1d3b022995e680d88022a4