minor symfony#7031 Capitalize the time designator (simoheinonen)

This PR was merged into the 2.7 branch.

Discussion
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Capitalize the time designator

Commits
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839c448 Capitalize the time designator

Author: wouterj

components/yaml/yaml_format.rst

@@ -158,7 +158,7 @@ YAML uses the ISO-8601 standard to express dates:
 
 .. code-block:: yaml
 
-    2001-12-14t21:59:43.10-05:00
+    2001-12-14T21:59:43.10-05:00
 
 .. code-block:: yaml