Commit Messages: Fix punctuation (#29060)

In Git commit message guidelines, the subject line shouldn't end with a period (".").

git/foundations_git/commit_messages.md

@@ -7,7 +7,7 @@ This lesson will explain the importance of good commit messages, how to write th
 This section contains a general overview of topics that you will learn in this lesson.
 
 - How to write a meaningful commit message.
-- Why meaningful commit messages are important
+- Why meaningful commit messages are important.
 - When to commit.
 
 ### Are commit messages so important they deserve their own lesson?
@@ -37,7 +37,7 @@ Effective commits consist of two separate parts: a subject, and a body:
 A brief summary of the change you made to the project.
 
 ```text
-This is the change I made to the codebase.
+This is the change I made to the codebase
 ```
 
 <div class="lesson-note lesson-note--tip" markdown=1>
@@ -94,7 +94,7 @@ There will come a time when you are working on a project and you FINALLY get som
 
 #### Tips and things to remember
 
-- Using VSCode as your text editor (you should have set this up in the Git Basics section) will allow you to easily make multi-line commit messages, easily see the character length of each line, and will allow you to use [VSCode spell check extensions](https://marketplace.visualstudio.com/items?itemName=streetsidesoftware.code-spell-checker) to make sure your spelling is correct
+- Using VSCode as your text editor (you should have set this up in the Git Basics section) will allow you to easily make multi-line commit messages, easily see the character length of each line, and will allow you to use [VSCode spell check extensions](https://marketplace.visualstudio.com/items?itemName=streetsidesoftware.code-spell-checker) to make sure your spelling is correct.
 - Use an active voice: "Fix card generator".
 - Avoid using vague commit messages such as "saved" or "updated".
 - Commit early and often!