docs(website): support GH page links to canonical src

[chalin]

Contributes to open-telemetry/opentelemetry.io#542

/cc @carlosalberto @mtwo @shelbyspees @austinlparker

While I can't (currently) show you a preview of this PR, you can see the corresponding change for OTel Java in action by clicking on the Edit this page and related links, from https://opentelemetry.io/docs/java/ and it's subpages.

@dyladan @obecny @vmarchaud: I see that this repo doesn't yet have a docs-update GitHub action. If you prefer, I can link OTel JS website_docs to the OTel website via a git submodule -- similar to what I did for Go in Link to OTel Go website_docs via submodule - open-telemetry/opentelemetry.io#690. That way you won't need to submit website_docs PRs.

Context: #2051

[codecov]

Codecov Report

Merging #2421 (dcf5621) into main (dfb597d) will decrease coverage by 0.36%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #2421      +/-   ##
==========================================
- Coverage   92.72%   92.36%   -0.37%     
==========================================
  Files         137      114      -23     
  Lines        4990     3901    -1089     
  Branches     1054      842     -212     
==========================================
- Hits         4627     3603    -1024     
+ Misses        363      298      -65     

Impacted Files	Coverage Δ
...emetry-core/src/platform/node/RandomIdGenerator.ts	87.50% <0.00%> (-6.25%)	⬇️
...opentelemetry-api-metrics/src/NoopMeterProvider.ts
...emetry-instrumentation-xml-http-request/src/xhr.ts
packages/opentelemetry-sdk-trace-web/src/types.ts
packages/opentelemetry-sdk-trace-web/src/utils.ts
...kages/opentelemetry-api-metrics/src/api/metrics.ts
...ation-xml-http-request/src/enums/AttributeNames.ts
...ry-exporter-collector/src/CollectorExporterBase.ts
...emetry-api-metrics/src/platform/node/globalThis.ts
...s/opentelemetry-instrumentation-fetch/src/fetch.ts
... and 14 more

[dyladan]

@dyladan @obecny @vmarchaud: I see that this repo doesn't yet have a docs-update GitHub action. If you prefer, I can link OTel JS website_docs to the OTel website via a git submodule -- similar to what I did for Go in Link to OTel Go website_docs via submodule - open-telemetry/opentelemetry.io#690. That way you won't need to submit website_docs PRs.

That sounds great! Keeping the website docs up to date isn't a hard task, but it is one more thing that needs to be remembered and can be forgotten each time we update the docs.

[chalin]

Hi all. Anything to be done before this can be approved and merged?

[dyladan]

We need another approver before we can merge

[obecny]

lgtm

[dyladan]

The browser test failure is completely unrelated. I'm going to merge.