[Docs] Restructure of Git Best Practices doc (#7231)

* Add "Resynchronizing an Out-of-Sync Git Branch" doc

* Update (Git) Best Practices doc title and filename

* Rename Branch Resync doc

* fork Best Practices doc into multiple files

* Add the doc list to Git Best Practices doc

* Update sidebar

* Update internal references

* Update sidebar - add subsection

* Update Your Fork's Master page title

* title case on Git Best Practices main doc

* ... and in the Resynchronizing a Branch doc

* Please read Part 1

I worked really hard on this, okay?

* Please use branches, too.

* suggestions by mtei

* change note about adding multiple files

* note that the name given the remote repo is arbitrary

* suggestions by fauxpark

* Git Best Practices -> Best Git Practices

Reads more naturally.

* rephrase hint block regarding remote name

* rework the resynchronization instructions per mtei

* use hint boxes for reference to Part 1 doc

I may be addicted to hint boxes. I'm sorry fauxpark. :cry:

* add some clarity about the upstream repo

* wordsmithing per mtei

* restyle the shell code blocks

Makes them more consistent to the other docs in this section.

1 files changed, 4 insertions, 1 deletions

diff --git a/docs/_summary.md b/docs/_summary.md
index 409df6d18..b6ee4a923 100644
--- a/docs/_summary.md
+++ b/docs/_summary.md
@@ -3,7 +3,10 @@
   * [Building Your First Firmware](newbs_building_firmware.md)
   * [Flashing Firmware](newbs_flashing.md)
   * [Testing and Debugging](newbs_testing_debugging.md)
-  * [Git Best Practices](newbs_best_practices.md)
+  * [Best Git Practices](newbs_git_best_practices.md)
+    * [Using Your Fork's Master](newbs_git_using_your_master_branch.md)
+    * [Resolving Merge Conflicts](newbs_git_resolving_merge_conflicts.md)
+    * [Resynchronizing a Branch](newbs_git_resynchronize_a_branch.md)
   * [Learning Resources](newbs_learn_more_resources.md)
 
 * [QMK Basics](README.md)