fix: prettify CSS result from the @bolt/build-tools before doing snapshot diff

(cherry picked from commit b47f2dc)

Author: sghoweri

packages/build-tools/__tests__/multi-lang/__snapshots__/index.js.snap

@@ -1,5 +1,7 @@
 const path = require('path');
 const fs = require('fs-extra');
+const prettier = require('prettier');
+const prettierConfig = { semi: false, parser: 'css' };
 
 const buildDir = require('./.boltrc.multi-lang.js').buildDir;
 
@@ -68,8 +70,9 @@ describe('Tests to confirm that the latest upcoming release of the @bolt/build-t
     };
 
     const cssFile = await getCSSData();
+    const prettyCss = await prettier.format(cssFile, prettierConfig);
 
-    expect(cssFile).toMatchSnapshot();
+    expect(prettyCss).toMatchSnapshot();
 
     const japaneseFontRule =
       'font-family:-apple-system,BlinkMacSystemFont,ヒラギノ角ゴ ProN,Hiragino Kaku Gothic ProN,游ゴシック,游ゴシック体,YuGothic,Yu Gothic,メイリオ,Meiryo,ＭＳ ゴシック,MS Gothic,HiraKakuProN-W3,TakaoExゴシック,TakaoExGothic,MotoyaLCedar,Droid Sans Japanese,sans-serif;';
@@ -124,6 +127,7 @@ describe('Tests to confirm that the latest upcoming release of the @bolt/build-t
       ),
     );
 
-    expect(cssFile).toMatchSnapshot();
+    const prettyCss = await prettier.format(cssFile, prettierConfig);
+    expect(prettyCss).toMatchSnapshot();
   });
 });

packages/build-tools/__tests__/multi-lang/index.js

@@ -35,7 +35,8 @@
     "jest-serializer-html": "^7.0.0",
     "now-storage": "^1.3.0",
     "puppeteer-core": "^1.17.0",
-    "raf": "^3.4.1"
+    "raf": "^3.4.1",
+    "prettier": "^1.18.2"
   },
   "publishConfig": {
     "access": "public"