Update HttpHeader schema

• add constraint: name, mapping_id and apply_to combinaison are unique
• value can be null and limit is 256 char now

requested review from @veniela

assigned to @simovin

added 1 commit

• 76823e3e - Update HttpHeader schema

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approved this merge request

@simovin Im not sure I understand the unique constraint in netbox. This is not really clear to. What is going to be unique ? I want to confirm it would be possible to have multiple headers with "apply_to" equal to "request" on a single mapping.

mentioned in commit 4e034a5e

merged