[Form customization] added block_name example.
[Form customization] fixed minor typos
feature #3818 [Form customization] added block_name example. (aitboudad)

This PR was merged into the 2.3 branch.

Discussion
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[Form customization] added block_name example.

| Q             | A
| ------------- | ---
| Doc fix?	 | yes
| New docs? | no
| Applies to | all
|Fixed tickets |	-

Commits
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512d5eb [Form customization] fixed minor typos
e423118 [Form customization] added block_name example.