Sanity checks for Kea 1.9.10 rc3

Please verify the packages and files according to "4. Sanity Checks" chapter on:
    https://wiki.isc.org/bin/view/QA/KeaReleaseProcess#4.%20Sanity%20Checks
and your imagination.
Before starting any checks, please state what check you are doing in a
thread/discussion (not as comment) in Sanity Checks issue in GitLab:
    
When you finish given check state in the same thread/discussion what is the result.
This way we know what is covered upfront and we can avoid repeating ourselves.

Release content is located on:
1) [tarballs] repo.isc.org in the following folders:
   /data/shared/sweng/kea/releases/1.9.10-rc3
   /data/shared/sweng/kea/releases/premium-1.9.10-rc3
   /data/shared/sweng/kea/releases/subscription-1.9.10-rc3

SHA256 (kea-1.9.10.tar.gz) = c3db991c6969ab06ff5c0fc2948de3a1d0293d5e1f6d7280cb551eb41516f922
SHA256 (kea-premium-1.9.10.tar.gz) = fcf51137a30ce953ed209093f55a763603c359d4bcb7f8722595de777df50a37
SHA256 (kea-subscription-1.9.10.tar.gz) = dd1339646a752a31d8e593dbe7c5ebefa82b08ea85b951aedc4776d13b2ee41e

2) [rpm/deb packages] on packages.isc.org, exact packages versions are stored here:
    https://jenkins.aws.isc.org/job/kea-dev/job/pkg/460/
    Release version is 1.9.10-r20210730172914 (please verify if it is this version while installing).
    Install instruction is here: https://wiki.isc.org/bin/view/QA/KeaReleaseProcess, chapter 4. Sanity Checks, point 9.