Closes gh-21015

See gh-24271

* pr/24271:
  Polish "Triggering a restart" formatting
  Document devtools restart with Maven/Gradle

Closes gh-24271

See gh-24271

Update the documentation to help avoid confusion for people who aren't
using an IDE.

See gh-24271

Improve documentation by adding a link from the "Error Handling" section
to the appendix.

Closes gh-24265

* pr/24306:
  Polish

Closes gh-24306

See gh-24306

Closes gh-24273

See gh-24292

See gh-24289

See gh-24286

See gh-24282

Closes gh-24366

Closes gh-24365

Closes gh-24364

Closes gh-24363

Closes gh-24362

Closes gh-24361

Closes gh-24360

Closes gh-24359

Closes gh-24358

Closes gh-24357

Closes gh-24356

Closes gh-24355

Closes gh-24354

Closes gh-24353

Closes gh-24352

Closes gh-24351

See gh-24344

This commit upgrades the docker image for CentOS to Centos 7.9 as
CentOs 6 is EOL since November 30. Given that CentOS 7 does no longer
support SysVinit, this commit also updates the integration tests to not
test this OS anymore.

Closes gh-24344

See gh-24337

This reverts commit 5a51b585.

Restore `HazelcastHealthIndicatorTests` which was accidentally replaced
with a version from 2.4.x.

See gh-24337

See gh-24337

See gh-24337

Closes gh-24337

Closes gh-11987

See gh-24276