Preserve whitespace on parsing JSON payload

More details - Out of scope observations section

When parsing sample payload for custom mapping on alerts HTTP integration form, white spaces of the pasted JSON are trimmed. It makes editing a condensed version pretty hard. The proposal is to preserve JSON in the form provided by the user.

Parsed version User provided
Screen_Shot_2021-03-24_at_13.47.41 Screen_Shot_2021-03-24_at_13.48.00
Edited by Olena Horal-Koretska