[roll] Roll fuchsia [sestarnix] Cleanup the userspace tests & framework a little

- Refactor the various attribute and SELinux API reading helpers
  for greater code re-use.
- Introduce a matcher for fit::result<int,string> values, to allow
  tests to write e.g. EXPECT_THAT(foo, IsOk(value)).
- Provide a PrintTo() overload for fit::result<E,T>, to allow tests
  to get nice output on failure from the IsOk() matcher.

Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1236086
Original-Revision: 4913f3623f2c1ceb99b94e3d03db7492bcfb830f
GitOrigin-RevId: 626b81c777c9a86e1c6846ccbaa9b398ba9cc1e1
Change-Id: Iee434f1448238eae009a5490d83fae94e04e1ce9

Author: Wez

stem

@@ -11,7 +11,7 @@
              githooks="integration/git-hooks"
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="07fc45fa97e61817d182e6d5f33961538431191e"/>
+             revision="4913f3623f2c1ceb99b94e3d03db7492bcfb830f"/>
   </projects>
   <hooks>
     <hook name="install-environment"