minor #14986 [Encore] fix typo fronts instead of fonts (nclsHart)

This PR was merged into the 5.2 branch.

Discussion
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[Encore] fix typo fronts instead of fonts

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Commits
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915b0d5 [Encore] fix typo fronts instead of fonts

Author: OskarStark

frontend/encore/url-loader.rst

@@ -1,4 +1,4 @@
-Inlining Images & Fronts in CSS
+Inlining Images & Fonts in CSS
 ===============================
 
 A simple technique to improve the performance of web applications is to reduce