Add basic VSCode configurations (run tests, debug)

We can now benefit from the standard debug gem integrated with the
Ruby LSP VSCode extension.

Author: maximerety

.vscode/extensions.json

@@ -0,0 +1,6 @@
+{
+  "recommendations": [
+    "ruby-syntax-tree.vscode-syntax-tree",
+    "shopify.ruby-lsp"
+  ]
+}

.vscode/launch.json

@@ -0,0 +1,11 @@
+{
+  "version": "0.2.0",
+  "configurations": [
+    {
+      "type": "ruby_lsp",
+      "request": "launch",
+      "name": "Debug test file",
+      "program": "ruby -Itest ${relativeFile}",
+    },
+  ]
+}

.vscode/tasks.json

@@ -0,0 +1,27 @@
+{
+  // See https://go.microsoft.com/fwlink/?LinkId=733558
+  // for the documentation about the tasks.json format
+  "version": "2.0.0",
+  "tasks": [
+    {
+      "group": "test",
+      "label": "Run all tests",
+      "type": "shell",
+      "command": "bundle exec rake test",
+      "problemMatcher": [],
+      "presentation": {
+        "clear": true
+      }
+    },
+    {
+      "group": "test",
+      "label": "Run tests for current file",
+      "type": "shell",
+      "command": "bundle exec rake test TEST=${file}",
+      "problemMatcher": [],
+      "presentation": {
+        "clear": true
+      }
+    }
+  ]
+}