Add documentation for dynamic route parameters in custom routes

[zimeg]

Summary

This PR adds supporting documentation to the "Adding custom HTTP routes" section for the enhancements made in #1785. The documentation links out to the official Express documentation for more details, and provides a simple example to showcase this feature.

Requirements

• I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.

[codecov]

Codecov Report

Merging #1791 (77337d8) into main (2b3b929) will not change coverage.
The diff coverage is n/a.

❗ Current head 77337d8 differs from pull request most recent head b740f97. Consider uploading reports for the commit b740f97 to get more accurate results

@@           Coverage Diff           @@
##             main    #1791   +/-   ##
=======================================
  Coverage   82.27%   82.27%           
=======================================
  Files          18       18           
  Lines        1523     1523           
  Branches      441      441           
=======================================
  Hits         1253     1253           
  Misses        172      172           
  Partials       98       98           

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[zimeg]

@seratch The requested updates have been made and the version number in these docs has been changed to v3.12.3. Thank you for looking at this, and please let me know if there are more changes to make!

[seratch]

The requested updates have been made and the version number in these docs has been changed to v3.12.3. Thank you for looking at this, and please let me know if there are more changes to make!

It might be confusing but I've moved this to the existing v3.12.3 and renamed it to v3.13.0 after that. So, the next version is till v3.13.0. The reason why I reused the existing one is that it already had 13 issues/PRs in it and I didn't want to move it one by one 😄

Either way, please forget the version number 3.12.3 -- you can make v3.13 release with these changes!

[seratch]

Looks good to me but I'd recommend merging this PR after releasing a new version including the feature addition

[zimeg]

It might be confusing but I've moved this to the existing v3.12.3 and renamed it to v3.13.0 after that.

@seratch Ahh I completely missed that! Sneaky yet sensible 😏 I'll hold off on merging until the new version is released 👍