fix: type directives import

[bartlomieju]

Fixes #2909

I'm not sure about the test though

CC @kitsonk

[kitsonk]

LGTM

[axetroy]

Should we add test cases to ensure that the parsing of the directives is correct?

eg.

interface TestCase {
  input: string;
  output?: DirectiveInfo;
  error?: string;
}

test(() => {
  // defined testcase
  const testcases = [
    {
      input: "// some typescript code",
      output: undefined
    },
    {
      input: `// @deno-types="./foo.d.ts"`,
      output: {
        path: "...",
        start: 0,
        end: 0
      }
    }
  ];

  for (const testcase of testcases) {
    // run parser function
  }
});

[kitsonk]

@axetroy at the moment we don't have unit tests for the compiler and related modules, mostly because they have no run-time presence to access via the unit tests... we are getting to the point though where that will become possible to load the modules in the runtime and unit test them, but I see adding (actually restoring) that functionality to be seperate from this PR.

[ry]

LGTM