docs: Replace obsolete GYP references with GN in docker_build and cobalt_evergreen_lite

[andrewsavage1]

Update documentation in docker_build.md and cobalt_evergreen_lite.md (and their corresponding site/docs/gen/ copies) to refer to GN instead of GYP for platform and configuration arguments.

Fixed: 482404018

[gemini-code-assist]

Code Review

This pull request updates the documentation across several files to reference the GN build system instead of GYP. The reviewer pointed out that since the build system is being updated to GN, the boolean configuration values in the documentation should also be updated from 1 to true to reflect GN conventions rather than GYP conventions.

[gemini-code-assist]

In GN, boolean arguments are set to true or false rather than 1 or 0 (which was the GYP convention). Since the documentation is being updated to refer to GN, we should also update the values to true.

Suggested change

	`sb_evergreen_compatible` and `sb_evergreen_compatible_lite` to `1`s in the `gn`
	`sb_evergreen_compatible` and `sb_evergreen_compatible_lite` to `true` in the `gn`

[gemini-code-assist]

In GN, boolean arguments are set to true or false rather than 1 or 0 (which was the GYP convention). Since the documentation is being updated to refer to GN, we should also update the values to true.

Suggested change

	`sb_evergreen_compatible` and `sb_evergreen_compatible_lite` to `1`s in the `gn`
	`sb_evergreen_compatible` and `sb_evergreen_compatible_lite` to `true` in the `gn`

[github-actions]

🤖 Gemini Suggested Commit Message

---

docs: Replace obsolete GYP references with GN

Update documentation in docker_build.md and cobalt_evergreen_lite.md,
along with their corresponding generated copies, to refer to GN
instead of GYP for platform and configuration arguments. GYP is
obsolete in the Cobalt build system.

Bug: None

---

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[hferreiro]

sb_evergreen_compatible has been replaced by is_starboard

[hferreiro]

@andrewsavage1 I just removed this references at #12486.