Fix CodeQL issues (graphql-dotnet#2824)

Fix bug: schema instance was registered incorrectly by AddSchema (gra…

…phql-dotnet#2801)

Bump Nito.AsyncEx.Context from 5.1.0 to 5.1.2 (graphql-dotnet#2666)

Bump coverlet.msbuild from 3.0.3 to 3.1.0 (graphql-dotnet#2613)

Remove deprecated functionaliaty from the new SystemTextJson.FromJson…

… methods (graphql-dotnet#2530)

Add additional deserialization extensions to GraphQL (graphql-dotnet#…

…2521)

DeprecationReason as computed property stored in Metadata (in applied…

…directives), also changes " to ' in some error messages (graphql-dotnet#2507)

Fix when building a schema with many type references (graphql-dotnet#…

…2466)

Fix argument type mapping regression (graphql-dotnet#2448)

Fix ToConstantCase to match 3.x semantics (graphql-dotnet#2424)