Update docs to include note about submodules & workspaces (#1279)

Author: reggi

content/packages-and-modules/introduction-to-packages-and-modules/about-packages-and-modules.mdx

@@ -39,6 +39,8 @@ Git URLs used for npm packages can be formatted in the following ways:
 
 The `commit-ish` can be any tag, sha, or branch that can be supplied as an argument to `git checkout`. The default `commit-ish` is `HEAD`.
 
+Installing any package directly from git will not install [git submodules](https://git-scm.com/book/en/v2/Git-Tools-Submodules) or workspaces.
+
 ## About modules
 
 A **module** is any file or directory in the `node_modules` directory that can be loaded by the Node.js `require()` function.