Use dynamically linked Haskell Language Server in direnv

[supersven]

This fixes the issues with HLS + Template Haskell ("This HLS binary does not support Template Haskell. Follow the instructions to build an HLS binary with support for Template Haskell. ")

Checklist

• [x] The PR Title explains the impact of the change.
• [x] The PR description provides context as to why the change should occur and what the code contributes to that effect. This could also be a link to a JIRA ticket or a Github issue, if there is one.
• [x] If this PR changes development workflow or dependencies, they have been A) automated and B) documented under docs/developer/. All efforts have been taken to minimize development setup breakage or slowdown for co-workers.
• [x] changelog.d contains the following bits of information (details):
  • [x] A file with the changelog entry in one or more suitable sub-sections. The sub-sections are marked by directories inside changelog.d.

[CLAassistant]

All committers have signed the CLA.