[FrameworkBundle] add missing attribute to XSD

The hinclude_default_template configuration option couldn't have been
set in XML configurations since it wasn't defined in the XML schema
definition.
bug #11633 [FrameworkBundle] add missing attribute to XSD (xabbuh)

This PR was merged into the 2.3 branch.

Discussion
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[FrameworkBundle] add missing attribute to XSD

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

The ``hinclude_default_template`` configuration option couldn't have been set in XML configurations since it wasn't defined in the XML schema definition.

Commits
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8a2b423 [FrameworkBundle] add missing attribute to XSD