docs/devel: Fixing broken link to development guide (#4085)
docs/devel: Fixing broken link to development guide (#4085)

* docs/devel: Fixing broken link to development guide

DEVELOPMENT.md linked to non-existing development guide URL at https://www.openpolicyagent.org/docs/edge/development/; changing link to https://www.openpolicyagent.org/docs/edge/contrib-development/.

Fixes: #4083
Signed-off-by: Johan Fylling <05c1a2f0e68460a354c87096e0c2d4ddf2525644@fylling.se>
open-policy-agent/opa,open-policy-agent/opa,open-policy-agent/opa,tsandall/opa,tsandall/opa,tsandall/opa,tsandall/opa,open-policy-agent/opa,tsandall/opa,open-policy-agent/opa,tsandall/opa,open-policy-agent/opa