Code improvements for NETCORE 3.1 compilation; Updated the editor config

Author: basicx-StrgV

src/.editorconfig

@@ -70,7 +70,7 @@ dotnet_style_prefer_inferred_anonymous_type_member_names = true
 dotnet_style_prefer_inferred_tuple_names = true
 dotnet_style_prefer_is_null_check_over_reference_equality_method = true
 dotnet_style_prefer_simplified_boolean_expressions = true
-dotnet_style_prefer_simplified_interpolation = true
+dotnet_style_prefer_simplified_interpolation = false
 
 # Field preferences
 dotnet_style_readonly_field = true

src/WGet.NET/Builder/WinGetAdminSettingBuilder.cs

@@ -47,7 +47,11 @@ public void AddRawContent(string rawContent)
             if (_hasShortenedContent)
             {
                 // Remove the char at the end of the shortened content.
+#if NETCOREAPP3_1_OR_GREATER
+                _rawContent = rawContent[..^1];
+#elif NETSTANDARD2_0
                 _rawContent = rawContent.Remove(rawContent.Length - 1);
+#endif
             }
             else
             {

src/WGet.NET/Builder/WinGetDirectoryBuilder.cs

@@ -50,7 +50,11 @@ public void AddRawContent(string rawContent)
             if (_hasShortenedContent)
             {
                 // Remove the char at the end of the shortened content.
+#if NETCOREAPP3_1_OR_GREATER
+                _rawContent = rawContent[..^1];
+#elif NETSTANDARD2_0
                 _rawContent = rawContent.Remove(rawContent.Length - 1);
+#endif
             }
             else
             {

src/WGet.NET/Builder/WinGetLinkBuilder.cs

@@ -49,7 +49,11 @@ public void AddRawContent(string rawContent)
             if (_hasShortenedContent)
             {
                 // Remove the char at the end of the shortened content.
+#if NETCOREAPP3_1_OR_GREATER
+                _rawContent = rawContent[..^1];
+#elif NETSTANDARD2_0
                 _rawContent = rawContent.Remove(rawContent.Length - 1);
+#endif
             }
             else
             {

src/WGet.NET/Builder/WinGetPackageBuilder.cs

@@ -3,8 +3,8 @@
 // https://github.com/basicx-StrgV/                 //
 //--------------------------------------------------//
 using System;
-using WGetNET.Parser;
 using WGetNET.Abstractions;
+using WGetNET.Parser;
 
 namespace WGetNET.Builder
 {
@@ -56,7 +56,11 @@ public void AddId(string id)
             if (_hasShortenedId)
             {
                 // Remove the char at the end of the shortened id.
+#if NETCOREAPP3_1_OR_GREATER
+                _id = id[..^1];
+#elif NETSTANDARD2_0
                 _id = id.Remove(id.Length - 1);
+#endif
             }
             else
             {

src/WGet.NET/Builder/WinGetPinnedPackageBuilder.cs

@@ -3,8 +3,8 @@
 // https://github.com/basicx-StrgV/                 //
 //--------------------------------------------------//
 using System;
-using WGetNET.Parser;
 using WGetNET.Abstractions;
+using WGetNET.Parser;
 
 namespace WGetNET.Builder
 {
@@ -89,7 +89,11 @@ public void AddId(string id)
             if (_hasShortenedId)
             {
                 // Remove the char at the end of the shortened id.
+#if NETCOREAPP3_1_OR_GREATER
+                _id = id[..^1];
+#elif NETSTANDARD2_0
                 _id = id.Remove(id.Length - 1);
+#endif
             }
             else
             {

src/WGet.NET/Helper/PathHelper.cs

@@ -57,7 +57,11 @@ public static string TrimLastPathPart(string path, PathType type)
 
             if (lastSeparatorIndex > -1)
             {
+#if NETCOREAPP3_1_OR_GREATER
+                return path[..lastSeparatorIndex];
+#elif NETSTANDARD2_0
                 return path.Remove(lastSeparatorIndex);
+#endif
             }
 
             return path;