admin: Update OpenImageIO Roadmap (#4469)

Check off the successfully raised dependencies.

Signed-off-by: Todica Ionut <todicaionut2000111@gmail.com>

docs/ROADMAP.md

@@ -32,23 +32,23 @@ here](https://github.com/AcademySoftwareFoundation/OpenImageIO/discussions/4151)
 
 See the [Dependency proposal wiki page](https://github.com/AcademySoftwareFoundation/OpenImageIO/discussions/4151)
 
-* [ ] Big required upgrades with potentially widespread impact on the code base
+* [x] Big required upgrades with potentially widespread impact on the code base
   - [x] C++17 [#4155](https://github.com/AcademySoftwareFoundation/OpenImageIO/issues/4155)
   - [x] Python 3.7 [#4157](https://github.com/AcademySoftwareFoundation/OpenImageIO/issues/4157)
-  - [ ] OpenEXR/Imath 3.1 [#4156](https://github.com/AcademySoftwareFoundation/OpenImageIO/issues/4156)
+  - [x] OpenEXR/Imath 3.1 [#4156](https://github.com/AcademySoftwareFoundation/OpenImageIO/issues/4156)
 
 * [ ] Miscellaneous optional upgrades whose changes will be very localized
 
   This isn't a complete list, nor do we need to do all of these, but the
   highest priorities are:
 
   - [ ] CMake 3.18 (from 3.15). Or possibly newer if there's a good reason? (3.19 or 3.20 are also reasonable.)
-  - [ ] OpenColorIO 2.0, or possibly 2.1 (from 1.1). Open for debate: should it be a required dependency rather than optional?
+  - [x] OpenColorIO 2.2, or possibly 2.1 (from 1.1). Open for debate: should it be a required dependency rather than optional?
   - [ ] fmt 8.0 (from 7.0), which has many improvements.
-  - [ ] GIFlib 5.0 (from 4.0), which adds thread safety.
-  - [ ] libheif 1.11 (from 1.3), which supports many additional features of that format.
-  - [ ] WebP 1.2 (from 0.6) which lets us use their exported CMake configs and retire FindWebP.cmake.
-  - [ ] pybind11 2.6 or 2.7 (from 2.4).
+  - [x] GIFlib 5.0 (from 4.0), which adds thread safety.
+  - [x] libheif 1.11 (from 1.3), which supports many additional features of that format.
+  - [x] WebP 1.2 (from 0.6) which lets us use their exported CMake configs and retire FindWebP.cmake.
+  - [x] pybind11 2.6 or 2.7 (from 2.4).
 
 
 - [x] [#4158](https://github.com/AcademySoftwareFoundation/OpenImageIO/issues/4158) Eliminate the last few places where we use Boost and eliminate it as a dependency.