Add NuGet license expression (Apache-2.0) and repository type

The package was missing <PackageLicenseExpression> metadata, resulting
in nupkgs without license info. Adds 'Apache-2.0' SPDX identifier and
explicit RepositoryType=git to align with main branch.

Author: CritasWang

src/Apache.IoTDB/Apache.IoTDB.csproj

@@ -6,6 +6,8 @@
         <Authors>eedalong, lausannel, MysticBoy, Aiemu, HTHou</Authors>
         <PackageProjectUrl>https://github.com/apache/iotdb-client-csharp</PackageProjectUrl>
         <RepositoryUrl>https://github.com/apache/iotdb-client-csharp</RepositoryUrl>
+        <PackageLicenseExpression>Apache-2.0</PackageLicenseExpression>
+        <RepositoryType>git</RepositoryType>
         <PackageReadmeFile>README.md</PackageReadmeFile>
         <Description>
 		C# client of Apache IoTDB.