Revert "Add a simple convenience test task runner for VSCode (#15417)" (#15705)

This reverts commit c8fd99fb33.

.vscode/tasks.json

@@ -1,24 +0,0 @@
-{
-  "version": "2.0.0",
-  "tasks": [
-    {
-      "command": "./.vscode/test.sh",
-      "windows": {
-        // TODO :S
-      },
-      "label": "test",
-      "type": "shell",
-      "group": {
-        "kind": "test",
-        "isDefault": true
-      },
-      "presentation": {
-        "echo": true,
-        "reveal": "always",
-        "focus": false,
-        "panel": "new"
-      },
-      "args": ["${relativeFile}"]
-    }
-  ]
-}

.vscode/test.sh

@@ -1,27 +0,0 @@
-#!/bin/bash
-
-if [[ $# -ne 1 ]]; then
-  echo "Invalid test target arguments.
-
-Please invoke test from VSCode via the workbench.action.tasks.test command."
-  exit 1
-fi
-
-if [[ "$1" != *.dart ]]; then
-  echo "Only .dart files can be tested by task in this repo."
-  exit 1
-fi
-
-echo "Testing $1..."
-
-if [[ "$1" == packages/flutter/test/* ]]; then
-  cd packages/flutter
-  ../../bin/flutter test ../../$1
-elif [[ "$1" == packages/flutter_tools/test/* ]]; then
-  bin/cache/dart-sdk/bin/dart $1
-else
-  echo "No test task configured for $1.
-
-Please edit .vscode/test.sh to configure new test types."
-  exit 1
-fi