Remove wrong CSS font-color property (#11047)

Fix CSS line-height property name

Remove unused longhand CSS padding properties

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## Description
This PR fixes a few CSS issues that were found during an analysis.

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## Related Issues

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  Link to the issue that is fixed by this PR (if there is one)
  e.g. Fixes #1234, Addresses #1234, Related to #1234, etc.
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Author: DanielRuf

examples/using-javascript-transforms/src/components/SiteLinks/style.css

@@ -25,5 +25,4 @@
 
 .blog-social ul > li:hover a > i {
   color: #444;
-  font-color: #444;
 }

examples/using-javascript-transforms/src/components/SiteNav/style.css

@@ -10,7 +10,7 @@
 }
 .blog-nav ul li a {
   font-size: 16px;
-  line-heigh: 26px;
+  line-height: 26px;
   margin-bottom: 26px;
   border-bottom: 0;
   font-weight: 400;

starters/default/src/components/layout.css

@@ -398,10 +398,6 @@ pre {
   margin-left: 0;
   margin-right: 0;
   margin-top: 0;
-  padding-bottom: 0;
-  padding-left: 0;
-  padding-right: 0;
-  padding-top: 0;
   margin-bottom: 1.45rem;
   font-size: 0.85rem;
   line-height: 1.42;