grep: update to 3.12

[Yang-Wei-Ting]

📦 Package Details

Maintainer: @Zokormazo

Description: Update grep to version 3.12. Also skip building doc, tests, and gnulib-tests.

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🧪 Run Testing Details

• OpenWrt Version: OpenWrt 24.10
• OpenWrt Target/Subtarget: NXP Layerscape / ARMv8 64-bit based boards
• OpenWrt Device:

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✅ Formalities

• [x] I have reviewed the CONTRIBUTING.md file for detailed contributing guidelines.

If your PR contains a patch:

• [ ] It can be applied using git am
• [x] It has been refreshed to avoid offsets, fuzzes, etc., using

  make package/<your-package>/refresh V=s
  

• [ ] It is structured in a way that it is potentially upstreamable _{(e.g., subject line, commit description, etc.) We must try to upstream patches to reduce maintenance burden.}