bug #8587 [Constraints/Collection] Add missing : and ~ in the yaml code block (NicolasDievart)

This PR was merged into the 2.7 branch.

Discussion
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[Constraints/Collection] Add missing : and ~ in the yaml code block

There were some typos in the yaml code block, some missing : and ~

Commits
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2778d33 Add missing : and ~ in the yaml code block

Author: weaverryan

reference/constraints/Collection.rst

@@ -95,7 +95,7 @@ following:
                         fields:
                             personal_email: Email
                             short_bio:
-                                - NotBlank
+                                - NotBlank: ~
                                 - Length:
                                     max:   100
                                     maxMessage: Your short bio is too long!
@@ -223,7 +223,7 @@ you can do the following:
                     - Collection:
                         fields:
                             personal_email:
-                                - Required
+                                - Required:
                                     - NotBlank: ~
                                     - Email: ~
                             alternate_email: