Replace conda-mambabuild with conda-build (#88)

These are now equivalent in behavior. However support for `conda-mambabuild` is being dropped. So switch to `conda-build`.

xref: rapidsai/build-planning#149

Authors:
  - https://github.com/jakirkham

Approvers:
  - James Lamb (https://github.com/jameslamb)
  - GALI PREM SAGAR (https://github.com/galipremsagar)

URL: #88

ci/build_python.sh

@@ -14,7 +14,7 @@ rapids-print-env
 rapids-logger "Begin py build"
 
 version=$(rapids-generate-version)
-RAPIDS_PACKAGE_VERSION=${version} rapids-conda-retry mambabuild \
+RAPIDS_PACKAGE_VERSION=${version} rapids-conda-retry build \
   conda/recipes/rapids-dask-dependency
 
 rapids-upload-conda-to-s3 python