remove uneeded specifications

Author: mattip

recipe/conda_build_config.yaml

@@ -1,11 +1,3 @@
-cuda_compiler_version:                          # [linux64]
-- None                                          # [linux64]
-docker_image:                                   # [linux64]
-- quay.io/condaforge/linux-anvil-cos7-x86_64    # [linux64]
-cudnn:                                          # [linux64]
-- undefined                                     # [linux64]
-cdt_name:                                       # [linux64]
-- cos7                                          # [linux64]
 c_compiler_version:                             # [linux64]
 - 13                                            # [linux64]
 cxx_compiler_version:                           # [linux64]