[TASK-9805] fix: certificate verification will fail on EDG

[GeneVT]

Summary

Fixes the CA certificates issue on EDGs when installing the local proxy.
Some EDGs fail certificate verification during tunnel setup due to outdated or missing CA certificates.
This change adds a step to update certificates during post-installation to ensure proper SSL handshake.

Gene has tested this adjustment using a snapshot .deb package with the newly post-installation script.

Checklist

• Pull Request title follows Conventional Commit specification format: type(scope): description
• Pull Request title is appended with Notion task ID in square brackets: [TASK-123]
• Branch has been rebased against latest merge destination branch; this is typically main or master.
• Linter (ESLint) and formatter (Prettier) has been applied on the code changes.
• There is test coverage on the changes made by this Pull Request.
• Documentation has been updated where necessary or comments were added where additional clarity is required.
• Reviewer has been assigned to this Pull Request.

[notion-workspace]

Verify Device Agent on EDG (finish transition from cloud to edge)

[AndrewJo]

Can we move it to debian/post-install to keep the file convention consistent between this repo and device-agent?

[GeneVT]

Can we move it to debian/post-install to keep the file convention consistent between this repo and device-agent?

Yes, sounds good!