scripts/make.fsx: gen normal nupkg & prerelease

This way we catch potential issues with the non-prerelease nuget
package before the git tag is pushed.

For example, the following warning:

```
/usr/lib/dotnet/sdk/6.0.127/Sdks/NuGet.Build.Tasks.Pack/build/NuGet.Build.Tasks.Pack.targets(221,5): error NU5104: A stable release of a package should not have a prerelease dependency. Either modify the version spec of
dependency "Fsdk [0.6.0--date20230530-1155.git-3bb8d08, )" or update the version field in the nuspec. [/__w/geewallet/geewallet/src/GWallet.Backend/GWallet.Backend.fsproj]
```

So let's enable 'warnaserror' in the 'dotnet pack' command
if the version to pack is even (e.g. 0.8) and ignore the
warning for now if it's odd (e.g. 0.7) like it currently
happens. Because even numbers map to "stableness" and odd
numbers to the opposite.

scripts/make.fsx

@@ -30,7 +30,7 @@ let GTK_FRONTEND_APP = sprintf "%s.Frontend.XF.Gtk" PASCALCASE_NAME
 let CONSOLE_FRONTEND_APP = sprintf "%s.Frontend.ConsoleApp" PASCALCASE_NAME
 let BACKEND_LIB = sprintf "%s.Backend" PASCALCASE_NAME
 
-let version = (Misc.GetCurrentVersion FsxHelper.RootDir).ToString()
+let currentVersion = Misc.GetCurrentVersion FsxHelper.RootDir
 
 type FrontendProject =
     | XF
@@ -477,7 +477,7 @@ match maybeTarget with
     let binDir = "bin"
     Directory.CreateDirectory(binDir) |> ignore
 
-    let zipNameWithoutExtension = sprintf "%s-v%s" script.Name version
+    let zipNameWithoutExtension = sprintf "%s-v%s" script.Name (currentVersion.ToString())
     let zipName = sprintf "%s.zip" zipNameWithoutExtension
     let pathToZip = Path.Combine(binDir, zipName)
     if (File.Exists (pathToZip)) then
@@ -685,41 +685,55 @@ match maybeTarget with
     let isTag =
         githubRef.StartsWith tagPrefix
 
-    let nugetVersion =
-        if isTag then
-            githubRef.Substring tagPrefix.Length
-        else
-            Network.GetNugetPrereleaseVersionFromBaseVersion version
     let backendDir = GetPathToBackend()
     let backendProj = Path.Combine(backendDir.FullName, BACKEND_LIB + ".fsproj")
 
-    let binaryConfig =
-        if isTag then
-            BinaryConfig.Release
-        else
-            BinaryConfig.Debug
-    let buildFlags = GetBuildFlags "dotnet" binaryConfig None
-    let allBuildFlags = sprintf "%s -property:Version=%s" buildFlags nugetVersion
-    Process.Execute(
-        {
-            Command = "dotnet"
-            Arguments = sprintf "pack %s %s" allBuildFlags backendProj
-        },
-        Echo.All
-    ).UnwrapDefault() |> ignore<string>
+    let createNugetPackageFile versionToPack =
+        let binaryConfig =
+            if isTag then
+                BinaryConfig.Release
+            else
+                BinaryConfig.Debug
+        let buildFlags = GetBuildFlags "dotnet" binaryConfig None
+        let allBuildFlags = sprintf "%s -property:Version=%s" buildFlags versionToPack
+        let maybeWarnAsError =
+            if currentVersion.Minor % 2 = 0 then
+                "-warnaserror"
+            else
+                String.Empty
+        Process.Execute(
+            {
+                Command = "dotnet"
+                Arguments = sprintf "pack %s %s %s" maybeWarnAsError allBuildFlags backendProj
+            },
+            Echo.All
+        ).UnwrapDefault() |> ignore<string>
 
-    let maybeNupkg =
         Directory.GetFiles(backendDir.FullName, "*.nupkg", SearchOption.AllDirectories)
         |> Seq.tryExactlyOne
 
+    // try first to create a non-prerelease package (as we want to fail fast instead of just fail at git tag push)
+    let maybeNupkg = createNugetPackageFile (currentVersion.ToString())
+    let nupkg =
+        match maybeNupkg with
+        | None -> failwith "File *.nupkg not found, did `dotnet pack` work properly?"
+        | Some nupkg ->
+            if isTag then
+                nupkg
+            else
+                File.Delete nupkg
+                let nugetVersion = Network.GetNugetPrereleaseVersionFromBaseVersion (currentVersion.ToString())
+                match createNugetPackageFile nugetVersion with
+                | None ->
+                    failwith "File *.nupkg not found (prerelease), did `dotnet pack` work properly?"
+                | Some nupkg ->
+                    nupkg
+
     let nugetApiKey = Environment.GetEnvironmentVariable "NUGET_API_KEY"
     if String.IsNullOrEmpty nugetApiKey then
         Console.WriteLine "NUGET_API_KEY not found, skipping push"
         Environment.Exit 0
-
-    match maybeNupkg with
-    | None -> failwith "File *.nupkg not found, did `dotnet pack` work properly?"
-    | Some nupkg ->
+    else
         let push() =
             Process.Execute(
                 {