minor #16788 [Runtime] Fix typo php-fpm => php-pm (wadjeroudi)

This PR was submitted for the 6.0 branch but it was merged into the 5.4 branch instead.

Discussion
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[Runtime] Fix typo php-fpm => php-pm

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Commits
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01eb82e Fix typo php-fpm => php-pm

Author: javiereguiluz

components/runtime.rst

@@ -6,7 +6,7 @@ The Runtime Component
 ======================
 
     The Runtime Component decouples the bootstrapping logic from any global state
-    to make sure the application can run with runtimes like PHP-FPM, ReactPHP,
+    to make sure the application can run with runtimes like PHP-PM, ReactPHP,
     Swoole, etc. without any changes.
 
 .. versionadded:: 5.3