Add super-linter + fix lint issues (#650)

* feat: bump `golangci-lint`, add `super-linter`, replace outdated linter

Bump `golangci-lint` version.
Add `super-linter` to lint other languages.
Go linter is disabled because it's currently broken:
https://github.com/github/super-linter/pull/370
Replacing `scopelint` with `exportloopref`: "[runner] The linter
'scopelint' is deprecated (since v1.39.0) due to: The repository of the
linter has been deprecated by the owner.  Replaced by exportloopref."
Fixed formatting in `.golangci.yml`
Add addtional linters:
  `misspell`: purely style, detects typos in comments
  `whitespace`: detects leading and trailing whitespace
  `goimports`: it's gofmt + checks unused imports

* fix: lint/fix `go` files

* fix: lint with `standardjs`

* fix: lint/fix with `markdownlint`, make template more verbose

* feat: add lint stuff to makefile

* fix: `UseGitIgnore` formatting

* fix: lint/fix `README.md`

Co-authored-by: Casey Lee <cplee@nektos.com>

act/common/git_test.go

@@ -40,7 +40,6 @@ func TestFindGitSlug(t *testing.T) {
 		assert.Equal(tt.provider, provider)
 		assert.Equal(tt.slug, slug)
 	}
-
 }
 
 func testDir(t *testing.T) string {