Bump dotnet version to 9.0

Author: wenbinf

.github/workflows/dotnet.yml

@@ -16,7 +16,7 @@ jobs:
     - name: Setup .NET
       uses: actions/setup-dotnet@v4
       with:
-        dotnet-version: 8.0.x
+        dotnet-version: 9.0.x
     - name: Restore dependencies
       run: dotnet restore
       working-directory: src

src/PodcastAPI.Tests/PodcastAPI.Tests.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
 
     <IsPackable>false</IsPackable>
   </PropertyGroup>

src/PodcastAPI/PodcastAPI.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <Version>1.1.6</Version>
     <Description>The Official .Net Library for Listen Notes Podcast API.</Description>

src/SampleApp/SampleApp.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>