enhance build.ps1 script (#15191)

* enhance build.ps1 script

* fix typo

eng/scripts/build.ps1

@@ -1,5 +1,5 @@
 #Requires -Version 7.0
-param([string]$filter, [switch]$clean, [switch]$vet, [switch]$generate, [switch]$skipBuild, [string]$config = "autorest.md", [string]$outputFolder)
+param([string]$filter, [switch]$clean, [switch]$vet, [switch]$generate, [switch]$skipBuild, [switch]$format, [switch]$tidy, [string]$config = "autorest.md", [string]$outputFolder)
 
 . $PSScriptRoot/meta_generation.ps1
 . $PSScriptRoot/get_module_dirs.ps1
@@ -34,6 +34,16 @@ function Process-Sdk ($path) {
         }
     }
 
+    if ($format) {
+        Write-Host "##[command]Executing gofmt -s -w . in " $path
+        gofmt -s -w $path
+    }
+
+    if ($tidy) {
+        Write-Host "##[command]Executing go mod tidy in " $path
+        go mod tidy
+    }
+
     if (!$skipBuild) {
         Write-Host "##[command]Executing go build -x -v ./... in " $path
         go build -x -v ./...