Fix typos (#3646)

docs/plugins/publishing.md

@@ -1,16 +1,16 @@
 ---
 id: publishing
 title: Publishing
-description: Documentation on Publishing NPM packages
+description: Documentation on Publishing npm packages
 ---
 
-## NPM
+## npm
 
-NPM packages are published through CI/CD in the
+npm packages are published through CI/CD in the
 [.github/workflows/master.yml](https://github.com/backstage/backstage/blob/master/.github/workflows/master.yml)
 workflow. Every commit that is merged to master will be checked for new versions
 of all public packages, and any new versions will automatically be published to
-NPM.
+npm.
 
 ### Creating a new release
 

docs/plugins/testing.md

@@ -234,7 +234,7 @@ This is especially true for edge cases!
 
 ## Non-React Classes
 
-Testing a Javascript object which is _not_ a React component follows a lot of
+Testing a JavaScript object which is _not_ a React component follows a lot of
 the same principles as testing objects in other languages.
 
 ### API Testing Principles
@@ -243,7 +243,7 @@ Testing an API involves verifying four things:
 
 1. Invalid inputs are caught before being sent to the server.
 2. Valid inputs translate into a valid browser request.
-3. Server response is translated into an expected Javascript object.
+3. Server response is translated into an expected JavaScript object.
 4. Server errors are handled gracefully.
 
 ### Mocking API Calls