minor #19219 Update runtime.rst (morrsky)

This PR was submitted for the 7.0 branch but it was merged into the 5.4 branch instead.

Discussion
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Update runtime.rst

typo PHP-PM:PHP-FPM

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Commits
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8962ac5 Update runtime.rst

Author: javiereguiluz

components/runtime.rst

@@ -2,7 +2,7 @@ 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-PM, ReactPHP,
+    to make sure the application can run with runtimes like PHP-FPM, ReactPHP,
     Swoole, etc. without any changes.
 
 .. versionadded:: 5.3