Support Visual Studio for Mac 17.5 preview 2

EF's Update-Database fails with an error:

Update-Database: The following exception occurred while retrieving
member "IsPathRooted": "GenericArguments[0],
'System.ReadOnlySpan`1[System.Char]', on 'System.Func`2[T,TResult]'
violates the constraint of type 'T'."

This seems to be related to VS Mac 17.5 running on .NET 7.

Build against VS Mac 17.5 preview 2.
Target .NET 7.0.
Update to PowerShell 7.3.0 which targets .NET 7.0.

Fixes #45

src/MonoDevelop.EnvDTE/MonoDevelop.EnvDTE.vbproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netstandard2.0</TargetFramework>
+    <TargetFramework>net7.0</TargetFramework>
     <RootNamespace></RootNamespace>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
     <SignAssembly>true</SignAssembly>

src/MonoDevelop.PackageManagement.Extensions/MonoDevelop.PackageManagement.Extensions.addin.xml

@@ -85,16 +85,16 @@
 		<Import file="libmi.dylib" />
 		<Import file="libpsl-native.dylib" />
 		<Import file="libpsrpclient.dylib" />
-		<Import file="runtimes/unix/lib/net6.0/Modules/Microsoft.PowerShell.Host/Microsoft.PowerShell.Host.psd1" />
-		<Import file="runtimes/unix/lib/net6.0/Modules/Microsoft.PowerShell.Management/Microsoft.PowerShell.Management.psd1" />
-		<Import file="runtimes/unix/lib/net6.0/Modules/Microsoft.PowerShell.Security/Microsoft.PowerShell.Security.psd1" />
-		<Import file="runtimes/unix/lib/net6.0/Modules/Microsoft.PowerShell.Utility/Microsoft.PowerShell.Utility.psd1" />
+		<Import file="runtimes/unix/lib/net7.0/Modules/Microsoft.PowerShell.Host/Microsoft.PowerShell.Host.psd1" />
+		<Import file="runtimes/unix/lib/net7.0/Modules/Microsoft.PowerShell.Management/Microsoft.PowerShell.Management.psd1" />
+		<Import file="runtimes/unix/lib/net7.0/Modules/Microsoft.PowerShell.Security/Microsoft.PowerShell.Security.psd1" />
+		<Import file="runtimes/unix/lib/net7.0/Modules/Microsoft.PowerShell.Utility/Microsoft.PowerShell.Utility.psd1" />
 	</Runtime>
 	<Dependencies>
-		<Addin id="Core" version="17.4"/>
-		<Addin id="Ide" version="17.4"/>
-		<Addin id="PackageManagement" version="17.4"/>
-		<Addin id="DotNetCore" version="17.4" />
+		<Addin id="Core" version="17.5"/>
+		<Addin id="Ide" version="17.5"/>
+		<Addin id="PackageManagement" version="17.5"/>
+		<Addin id="DotNetCore" version="17.5" />
 	</Dependencies>
 
 	<Extension path="/MonoDevelop/Ide/Composition">

src/MonoDevelop.PackageManagement.Extensions/MonoDevelop.PackageManagement.Extensions.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <Import Project="MonoDevelop.References.props" />
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net7.0</TargetFramework>
     <RootNamespace>MonoDevelop.PackageManagement</RootNamespace>
     <SignAssembly>true</SignAssembly>
     <PublicSign>True</PublicSign>
@@ -53,8 +53,8 @@
     </None>
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="6.0.0" />
-    <PackageReference Include="Microsoft.Extensions.ObjectPool" Version="6.0.0" />
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.3.0-1.final" />
+    <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="7.0.0" />
+    <PackageReference Include="Microsoft.Extensions.ObjectPool" Version="7.0.0" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.4.0-4.final" />
   </ItemGroup>
 </Project>

src/MonoDevelop.PackageManagement.PowerShell.Cmdlets/MonoDevelop.PackageManagement.PowerShell.Cmdlets.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net7.0</TargetFramework>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
     <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
     <OutputPath>..\..\bin</OutputPath>

src/MonoDevelop.PackageManagement.PowerShell/MonoDevelop.PackageManagement.PowerShell.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net7.0</TargetFramework>
     <SignAssembly>true</SignAssembly>
     <PublicSign>True</PublicSign>
     <AssemblyOriginatorKeyFile>..\MonoDevelop-Public.snk</AssemblyOriginatorKeyFile>
@@ -9,7 +9,7 @@
     <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Microsoft.PowerShell.SDK" Version="7.2.3" />
+    <PackageReference Include="Microsoft.PowerShell.SDK" Version="7.3.0" />
   </ItemGroup>
   <ItemGroup>
     <Reference Include="Microsoft.VisualStudio.Interop">