doc: Add Self Observability service discovery (k8s)

[wankai123]

• If this pull request closes/resolves/fixes an existing issue, replace the issue number. Closes Add doc about OTEL + OAP Self-observability #7259.
• Update the CHANGES log.

[kezhenxu94]

And for docs updates, I think it's better to loop @wingwong-knh in to review when the docs are updated in PR rather than review the whole docs after they're merged

[codecov]

Codecov Report

Merging #7339 (947339a) into master (002f4c2) will increase coverage by 8.52%.
The diff coverage is 54.97%.

❗ Current head 947339a differs from pull request most recent head 08fa5ed. Consider uploading reports for the commit 08fa5ed to get more accurate results

@@             Coverage Diff              @@
##             master    #7339      +/-   ##
============================================
+ Coverage     50.35%   58.88%   +8.52%     
- Complexity     2692     4373    +1681     
============================================
  Files           740     1029     +289     
  Lines         18265    26469    +8204     
  Branches       1766     2627     +861     
============================================
+ Hits           9198    15585    +6387     
- Misses         8337     9509    +1172     
- Partials        730     1375     +645     

Impacted Files	Coverage Δ
...walking/apm/commons/datacarrier/buffer/Buffer.java	71.42% <ø> (+71.42%)	⬆️
...commons/datacarrier/common/AtomicRangeInteger.java	50.00% <ø> (ø)
...tacarrier/partition/ProducerThreadPartitioner.java	0.00% <ø> (ø)
.../apache/skywalking/apm/util/ConfigInitializer.java	64.04% <0.00%> (+8.48%)	⬆️
.../apache/skywalking/apm/util/StringFormatGroup.java	0.00% <0.00%> (ø)
.../commands/executor/ProfileTaskCommandExecutor.java	7.69% <0.00%> (ø)
.../apm/agent/core/context/ids/GlobalIdGenerator.java	68.18% <0.00%> (+5.68%)	⬆️
...alking/apm/agent/core/context/tag/AbstractTag.java	35.00% <0.00%> (-28.64%)	⬇️
.../agent/core/context/trace/AbstractTracingSpan.java	45.45% <0.00%> (+4.88%)	⬆️
...alking/apm/agent/core/context/trace/EntrySpan.java	53.57% <0.00%> (ø)
... and 895 more

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[wu-sheng]

And for docs updates, I think it's better to loop @wingwong-knh in to review when the docs are updated in PR rather than review the whole docs after they're merged

I am not sure whether @wingwong-knh is available. Wing, if you are, please take a look.

[wu-sheng]

Thanks for fixing this

[wingwong-knh]

And for docs updates, I think it's better to loop @wingwong-knh in to review when the docs are updated in PR rather than review the whole docs after they're merged

I am not sure whether @wingwong-knh is available. Wing, if you are, please take a look.

Indeed, for now I'm not sure if I can keep up with the daily updates! In the future, once all docs have been gone through once, I can start reviewing the updates in PR. For now, I'm only halfway through the backend doc (will up my pace!) For this particular doc, I will need to review from scratch.

[wu-sheng]

And for docs updates, I think it's better to loop @wingwong-knh in to review when the docs are updated in PR rather than review the whole docs after they're merged

I am not sure whether @wingwong-knh is available. Wing, if you are, please take a look.

Indeed, for now I'm not sure if I can keep up with the daily updates! In the future, once all docs have been gone through once, I can start reviewing the updates in PR. For now, I'm only halfway through the backend doc (will up my pace!) For this particular doc, I will need to review from scratch.

Take your time. I know you are busy. We are going to continue, you could be back and polish the doc.