Return task so await triggers on the async variants (#94)

Co-authored-by: Oleg Zhuk <zhukoo@gmail.com>
Co-authored-by: amo <asmorogov@gmail.com>
Co-authored-by: vc-ci <ci@virtocommerce.com>

src/VirtoCommerce.Build/PlatformTools/ModulesInstallerBase.cs

@@ -9,14 +9,12 @@ public virtual Task Install(ModuleSource source)
         {
             try
             {
-                InnerInstall(source);
+                return InnerInstall(source);
             }
             catch (Exception exception)
             {
                 throw new ModuleInstallationException("Error while module installation", exception);
             }
-
-            return Task.CompletedTask;
         }
 
         protected abstract Task InnerInstall(ModuleSource source);