[vscodium.install] Remove unnecessary dependency

[vairag22]

Issue: VSCodium has an unnecessary dependency on DotNet4.5.2 package.

Details:

• Since version 1.78.1, both VSCode and its fork VSCodium do not require DotNet4.5.2.
• VSCode has already removed the dependency from their package.

Testing: There was no difference when running VSCodium after by forcefully removing DotNot4.5.2 on my machine.

[vairag22]

I believe removing this line from vscodium.install/vscodium.install.nuspec will suffice:
<dependency id="dotnet4.5.2" version="4.5.2.20140902" />

Opened a PR #57. Please review.

[Thilas]

Thanks for raising this issue. It will be fixed on this other PR (#58) where I'm fixing other similar issues.