[improve][websocket] Add ping support

[nodece]

Motivation

When the WebSocket connection is idle timeout, the server disconnects the client. We need to keep alive between the client and the server.

There are two options:

1. Increasing the idle timeout, but be very unfriendly to users who are not sensitive to time
2. Sending the ping frame to the client

Some client(browser) doesn't support sending the ping frame to the server, which causes idle timeout, so we only add enable ping feature on the server.

Note: The Jetty automatically processes ping/pong frames from the client by default.

Modifications

• Implement sending the ping frame to the client
• Add webSocketPingDurationSeconds config to enable the ping feature

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

Matching PR in forked repository

PR in forked repository:

[nodece]

Ping @poorbarcode

[Technoboy-]

LGTM

[codecov-commenter]

Codecov Report

Merging #19203 (b6c6471) into master (246c270) will decrease coverage by 0.45%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master   #19203      +/-   ##
============================================
- Coverage     43.01%   42.56%   -0.46%     
- Complexity    10167    10304     +137     
============================================
  Files           747      773      +26     
  Lines         72255    74509    +2254     
  Branches       7786     8031     +245     
============================================
+ Hits          31080    31714     +634     
- Misses        37577    39077    +1500     
- Partials       3598     3718     +120     

Flag	Coverage Δ
unittests	42.56% <ø> (-0.46%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...g/apache/pulsar/broker/service/StreamingStats.java	0.00% <0.00%> (-83.79%)	⬇️
...sar/broker/stats/metrics/ManagedLedgerMetrics.java	23.88% <0.00%> (-76.12%)	⬇️
...rvice/schema/KeyValueSchemaCompatibilityCheck.java	21.62% <0.00%> (-45.95%)	⬇️
...ker/service/schema/exceptions/SchemaException.java	60.00% <0.00%> (-40.00%)	⬇️
...lsar/broker/service/InMemoryRedeliveryTracker.java	58.82% <0.00%> (-35.30%)	⬇️
...ersistentStickyKeyDispatcherMultipleConsumers.java	18.13% <0.00%> (-34.32%)	⬇️
...ervice/persistent/MessageRedeliveryController.java	38.33% <0.00%> (-31.67%)	⬇️
...ulsar/utils/ConcurrentBitmapSortedLongPairSet.java	38.88% <0.00%> (-20.38%)	⬇️
.../org/apache/pulsar/broker/lookup/LookupResult.java	56.66% <0.00%> (-20.00%)	⬇️
...ulsar/broker/namespace/NamespaceEphemeralData.java	68.18% <0.00%> (-18.19%)	⬇️
... and 88 more

[nodece]

/pulsarbot rerun-failure-checks

[nodece]

Remove release/2.9.5, using #19245 instead.