fix: Integrate intercom messaging platform, change button colors #212

Description

Currently "Chat with us" button on the Contact page for the postgres website doesn't open the intercom chat banner.

Related issue

https://gitlab.com/postgres-ai/platform/-/issues/212

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Checklist

• the MR description has been reviewed
• this MR contains text changes and they have been reviewed OR there are no texts changes
• this MR contains GUI/CLI changes and they have been reviewed OR there are no GUI/CLI changes
• this MR contains API changes and they have been reviewed OR there are no API changes