FIX | Add Component Model annotations to SqlConnectionStringBuilder class in netcore's src folder

[JRahnama]

fixes #1142

[JRahnama]

Just an update here, I manually added the partial class of StringsHelper with all the needed constant strings inside it. In netfx there is a script named GenerateResourceStringsSource.ps1 and runs BeforeTargets="CoreCompile" which is called by GenerateResourceStringsSource.targets and it adds the partial class of StringsHelper inside each output directory in obj folder as Strings.ResourceNames.cs. In netcore, running the powershell script comes up with some issues on Linux machines. One of the options that could be investigated in future, when we have localization for netcore available, is MetadataTypeAttribute, which could be added to SqlConnectionStringBuilder.Windows and make sure this is only called on Windows OSs. The only problem with this class is netcoreapp2.1 which does not support it, however netcoreapp2.1 will come to EOL in August 2021 and that wont be problem anymore. We will look for other options when get to it.

[cheenamalhotra]

Just a tiny change, rest looks good to me 👍

[DavoudEshtehari]

Here are my observation of some types:
Properties descriptions seem good. 👏
But categories need some modifications.

Net Core	Net fx

[JRahnama]

Here are my observation of some types:
Properties descriptions seem good. 👏
But categories need some modifications.

I have added as many as possible. In some cases the base classes such as DataAdapter are adding those meta tags in netfx and in netcore those base classes do not have them. In order to do so we have to add them manually and it requires adding the strings to string.resx, I changed as many as I could. At some other places such SqlDataAdapter AcceptChangesDuringFill is in the base class and we have no control over them.

[DavoudEshtehari]

I believe these changes are enough for this PR.