Set intellisense defaults

[majastrz]

Set the following IntelliSense defaults for Bicep language in the VS code extension:

• Choose first selection in completion list (we have observed strange VS code behavior with other settings)
• Allow completions to work inside an active snippet
• Disables text-based completions.

This fixes #882

[codecov-io]

Codecov Report

Merging #1019 (3b5667c) into main (a0a38b2) will increase coverage by 0.46%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1019      +/-   ##
==========================================
+ Coverage   94.26%   94.72%   +0.46%     
==========================================
  Files         328      324       -4     
  Lines       15810    15670     -140     
  Branches       12        0      -12     
==========================================
- Hits        14903    14844      -59     
+ Misses        907      826      -81     

Flag	Coverage Δ
dotnet	94.72% <ø> (-0.10%)	⬇️
typescript	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...cep.Core.UnitTests/FileSystem/FileResolverTests.cs	79.31% <0.00%> (-20.69%)	⬇️
.../Bicep.Core.UnitTests/Assertions/BaselineHelper.cs	63.63% <0.00%> (-15.91%)	⬇️
src/Bicep.Core.UnitTests/Utils/CompilerFlags.cs	20.00% <0.00%> (-13.34%)	⬇️
src/Bicep.Core/FileSystem/PathHelper.cs	96.15% <0.00%> (-3.85%)	⬇️
...Bicep.Core.UnitTests/FileSystem/PathHelperTests.cs	100.00% <0.00%> (ø)
src/vscode-bicep/src/extension.ts
src/vscode-bicep/src/language/client.ts
src/vscode-bicep/src/utils/telemetry.ts
src/vscode-bicep/src/utils/logger.ts