Adds support for the following new WebGL2 GetParameter values:

- `MAX_ELEMENT_INDEX`
- `MAX_ELEMENTS_INDICES`
- `MAX_ELEMENTS_VERTICES`
- `MAX_FRAGMENT_INPUT_COMPONENTS`
- `MAX_SAMPLES`
- `MAX_SERVER_WAIT_TIMEOUT`
- `MAX_TEXTURE_LOD_BIAS`
- `MAX_VARYING_COMPONENTS`
- `MAX_VERTEX_OUTPUT_COMPONENTS`

See: https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.2