minor symfony#11958 Grammar/Typo fix in a warning box (AnnoyingTechnology)

This PR was submitted for the 4.3 branch but it was merged into the 3.4 branch instead (closes symfony#11958).

Discussion
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Grammar/Typo fix in a warning box

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Commits
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47e8880 Grammar/Typo fix in a warning box

Author: javiereguiluz

components/finder.rst

@@ -58,7 +58,7 @@ the Finder instance.
 
     The ``Finder`` object doesn't reset its internal state automatically.
     This means that you need to create a new instance if you do not want
-    get mixed results.
+    to get mixed results.
 
 .. caution::