Auto merge of #7409 - xFrednet:5394-vs-code-tasks, r=giraffate,flip1995

Added `cargo dev setup vscode-tasks` for simplicity

This PR adds a setup command to `clippy dev` that installs tasks into the Clippy vscode workspace. These might be useful as they be used via shortcuts and are accessible over the GUI. The available tasks are:
* `cargo check` (standard Linux shortcut `[ctrl] + [shift] + b`)
* `cargo dev fmt`
* `cargo uitest` (with a comment how to add the `TESTNAME` environment value)
* `cargo test`
* `cargo dev bless`

---

changelog: none

only internal changes again. cc #5394

r? `@flip1995` This should be pretty much the same as the other `cargo dev setup` commands. Would you mind reviewing this? 🙃

clippy_dev/src/main.rs

@@ -43,11 +43,13 @@ fn main() {
                     .expect("this field is mandatory and therefore always valid"),
             ),
             ("git-hook", Some(matches)) => setup::git_hook::install_hook(matches.is_present("force-override")),
+            ("vscode-tasks", Some(matches)) => setup::vscode::install_tasks(matches.is_present("force-override")),
             _ => {},
         },
         ("remove", Some(sub_command)) => match sub_command.subcommand() {
             ("git-hook", Some(_)) => setup::git_hook::remove_hook(),
             ("intellij", Some(_)) => setup::intellij::remove_rustc_src(),
+            ("vscode-tasks", Some(_)) => setup::vscode::remove_tasks(),
             _ => {},
         },
         ("serve", Some(matches)) => {
@@ -181,6 +183,17 @@ fn get_clap_config<'a>() -> ArgMatches<'a> {
                                 .help("Forces the override of an existing git pre-commit hook")
                                 .required(false),
                         ),
+                )
+                .subcommand(
+                    SubCommand::with_name("vscode-tasks")
+                        .about("Add several tasks to vscode for formatting, validation and testing")
+                        .arg(
+                            Arg::with_name("force-override")
+                                .long("force-override")
+                                .short("f")
+                                .help("Forces the override of existing vscode tasks")
+                                .required(false),
+                        ),
                 ),
         )
         .subcommand(
@@ -188,6 +201,7 @@ fn get_clap_config<'a>() -> ArgMatches<'a> {
                 .about("Support for undoing changes done by the setup command")
                 .setting(AppSettings::ArgRequiredElseHelp)
                 .subcommand(SubCommand::with_name("git-hook").about("Remove any existing pre-commit git hook"))
+                .subcommand(SubCommand::with_name("vscode-tasks").about("Remove any existing vscode tasks"))
                 .subcommand(
                     SubCommand::with_name("intellij")
                         .about("Removes rustc source paths added via `cargo dev setup intellij`"),