Add support for RGB2Lab and Lab2RGB conversion in cvtcolor

[//]: # "SPDX-FileCopyrightText: Copyright (c) 2022-2023 NVIDIA CORPORATION & AFFILIATES. All rights reserved." [//]: # "SPDX-License-Identifier: Apache-2.0" [//]: # "" [//]: # "Licensed under the Apache License, Version 2.0 (the 'License');" [//]: # "you may not use this file except in compliance with the License." [//]: # "You may obtain a copy of the License at" [//]: # "http://www.apache.org/licenses/LICENSE-2.0" [//]: # "" [//]: # "Unless required by applicable law or agreed to in writing, software" [//]: # "distributed under the License is distributed on an 'AS IS' BASIS" [//]: # "WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied." [//]: # "See the License for the specific language governing permissions and" [//]: # "limitations under the License." **Is your feature request related to a problem? Please describe.** I would like to convert RGB images to the Lab color space and back again **Describe the solution you'd like** I would like cvcuda.cvtcolor in the Python API to support conversions using cvcuda.ColorConversion.RGB2Lab cvcuda.ColorConversion.Lab2RGB **Describe alternatives you've considered** A common need in cv pipelines is color matching across multiple cameras which may have different lighting and exposure conditions. The Lab color space offers superior color matching capability due to it's alignment with human perception of differences in colors. HSV is not as linear, but is a fallback option. **Additional context** OpenCV's CUDA module implements a variety of color conversions to and from the Lab color space.