[Resources.Gcp] Replace .NET 6 target with .NET 8 (open-telemetry#2167)

Co-authored-by: joegoldman2 <[email protected]>
Co-authored-by: Mikel Blanchard <[email protected]>

Author: joegoldman2

src/OpenTelemetry.Resources.Gcp/OpenTelemetry.Resources.Gcp.csproj

@@ -1,13 +1,14 @@
 <Project Sdk="Microsoft.NET.Sdk">
+
   <PropertyGroup>
-    <TargetFrameworks>net6.0;netstandard2.0</TargetFrameworks>
-    <Description>OpenTelemetry Resource Detectors for Google Cloud Platform environments</Description>
+    <TargetFrameworks>net8.0;$(NetStandardMinimumSupportedVersion)</TargetFrameworks>
+    <Description>OpenTelemetry Resource Detectors for Google Cloud Platform environments.</Description>
     <PackageTags>$(PackageTags);ResourceDetector</PackageTags>
     <MinVerTagPrefix>Resources.Gcp-</MinVerTagPrefix>
   </PropertyGroup>
 
-  <!--Do not run Package Baseline Validation as this package has never released a stable version.
-  Remove this property once we have released a stable version and add PackageValidationBaselineVersion property.-->
+  <!-- Do not run Package Baseline Validation as this package has never released a stable version.
+  Remove this property once we have released a stable version and add PackageValidationBaselineVersion property. -->
   <PropertyGroup>
     <DisablePackageBaselineValidation>true</DisablePackageBaselineValidation>
   </PropertyGroup>
@@ -24,4 +25,5 @@
     <Compile Include="$(RepoRoot)\src\Shared\Guard.cs" Link="Includes\Guard.cs" />
     <Compile Include="$(RepoRoot)\src\Shared\ResourceSemanticConventions.cs" Link="Includes\ResourceSemanticConventions.cs" />
   </ItemGroup>
+
 </Project>

test/OpenTelemetry.Resources.Gcp.Tests/OpenTelemetry.Resources.Gcp.Tests.csproj

@@ -1,10 +1,10 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <Description>Unit test project for GCP Detector for OpenTelemetry</Description>
     <!-- OmniSharp/VS Code requires TargetFrameworks to be in descending order for IntelliSense and analysis. -->
-    <TargetFrameworks>$(SupportedNetTargets)</TargetFrameworks>
+    <TargetFrameworks>$(SupportedNetTargetsWithoutNet6)</TargetFrameworks>
     <TargetFrameworks Condition="$(OS) == 'Windows_NT'">$(TargetFrameworks);$(NetFrameworkMinimumSupportedVersion)</TargetFrameworks>
+    <Description>Unit test project for GCP Detector for OpenTelemetry.</Description>
   </PropertyGroup>
 
   <ItemGroup>