Summary:
Java PG regress tests run schedules and normally report the names of
failed tests within those schedules.  The logic to collect failed tests
uses a regex over the test output.  Ever since the regex was created
(commit b7c49abdd60bc5661ed94c5d794ffdbff98e6b70), it did not properly
handle tests with dots in them, such as "collate.icu.utf8".  Such test
names were rare until commit b7b7cf040343733f98f057bb3af7194052ee30b9
changed pretty much all tests that YB runs to have dots in them.

Fix the regex to handle dots.  While at it, fix the adjacent comment as
well to be up-to-date with b7b7cf040343733f98f057bb3af7194052ee30b9.

Jira: DB-15456

Test Plan:
Backport-through: 2.20
Close: #26129
Jenkins: java only
Original commit: be5c9a7936fb3fe26e70fc1630e50049c7c93f25 / D42035

Reviewers: kfranz

Reviewed By: kfranz

Subscribers: kfranz

Differential Revision: https://phorge.dev.yugabyte.com/D42058