[Androidx Health] Bump the minSdkVersion to 30.
[Androidx Health] Bump the minSdkVersion to 30.

Health Services is not currently supported on older
SDK versions so leaving minSdkVersion 26 was misleading
to developers.

Test: ./gradlew :health:health-services-client:assemble
Relnote: N/A
Change-Id: I92672ae0b225a934f00a9ccd40290acbbd1a7d19

androidx/androidx,AndroidX/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx