git: openjdk/jcstress: CODETOOLS-7902918: jcstress: Replace the relevant uses of HashMultiset with Counter

[duke]

Changeset: 5012b897
Author:    Aleksey Shipilëv <shade at redhat.com>
Committer: GitHub <noreply at github.com>
Date:      2021-05-04 15:00:54 +0000
URL:       https://git.openjdk.java.net/jcstress/commit/5012b897e4e667fc4601770fa43247451b3e0b1d

CODETOOLS-7902918: jcstress: Replace the relevant uses of HashMultiset with Counter


! jcstress-core/src/main/java/org/openjdk/jcstress/infra/collectors/TestResult.java
! jcstress-core/src/main/java/org/openjdk/jcstress/infra/grading/ReportUtils.java
! jcstress-core/src/main/java/org/openjdk/jcstress/util/Counter.java
! jcstress-core/src/test/java/org/openjdk/jcstress/util/CounterTest.java