Added missing default dependencies for using vcpkg manifest

[Codinablack]

Pull Request Prelude

• [x] I have followed proper The Forgotten Server code styling.
• [x] I have read and understood the contribution guidelines before making this PR.
• [x] I am aware that this PR may be closed if the above-mentioned criteria are not fulfilled.

Changes Proposed

Issues addressed: When using manifest mode with vcpkg, you are unable to build as the features called "http" and "unit-tests" are not enabled by default, and therefore their dependencies are not downloaded, yet files that use them are included in the build.

To fix that, we just enable these features by default.

[ranisalt]

There's something wrong with your setup, since these features will be enabled when you invoke CMake with the vcpkg preset, and you never need to enable them in a separate step

[Codinablack]

Made the requested adjustment