Prevent public builds on non-release branches without --force option

Author: gfraiteur

src/PostSharp.Engineering.BuildTools/Build/BuildCommand.cs

@@ -62,6 +62,22 @@ public static bool Execute( BuildContext context, BuildSettings settings )
                 dateTag = DateTime.Now;
             }
 
+            // Refuse to perform a public build on a non-release branch.
+            if ( configuration == BuildConfiguration.Public && !settings.Force )
+            {
+                if ( !GitHelper.TryGetCurrentBranch( context, out var currentBranch ) )
+                {
+                    return false;
+                }
+
+                if ( !currentBranch.StartsWith( "release/", StringComparison.OrdinalIgnoreCase ) )
+                {
+                    context.Console.WriteError( "Cannot perform a public build on a non-release branch without --force." );
+
+                    return false;
+                }
+            }
+
             // Build dependencies.
             DependenciesConfigurationFile? dependenciesOverrideFile;