minor #9 feat: setup Yarn workspaces (Kocal)

This PR was squashed before being merged into the main branch.

Discussion
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feat: setup Yarn workspaces

Hi! 👋

Since this repository is a multi-packages repository, I thought it would be interesting and useful to use Yarn workspaces on it (since we use Yarn).

This will prevent some code duplications (e.g.: in the CI) and make it more "DX-friendly" if you want to build, test, lint (... 👀) all packages in one time:
![Capture d’écran de 2020-12-05 10-30-07](https://user-images.githubusercontent.com/2103975/101239050-e0639c80-36e4-11eb-98a9-72298e6124a6.png)

What do you think?
Thanks!

Commits
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fb65d0f feat: setup Yarn workspaces

Author: tgalopin

.github/workflows/test.yaml

@@ -85,23 +85,5 @@ jobs:
         runs-on: ubuntu-latest
         steps:
             - uses: actions/checkout@master
-            - name: Chartjs
-              run: |
-                  cd src/Chartjs/Resources/assets
-                  yarn
-                  yarn test
-            - name: Cropperjs
-              run: |
-                  cd src/Cropperjs/Resources/assets
-                  yarn
-                  yarn test
-            - name: Dropzone
-              run: |
-                  cd src/Dropzone/Resources/assets
-                  yarn
-                  yarn test
-            - name: LazyImage
-              run: |
-                  cd src/LazyImage/Resources/assets
-                  yarn
-                  yarn test
+            - run: yarn
+            - run: yarn test

.gitignore

@@ -1 +1,4 @@
 .php_cs.cache
+node_modules
+yarn.lock
+yarn-error.log

package.json

@@ -0,0 +1,8 @@
+{
+    "private": true,
+    "workspaces": ["src/*/Resources/assets"],
+    "scripts": {
+        "build": "yarn workspaces run build",
+        "test": "yarn workspaces run test"
+    }
+}