Remove duplicate librmm runtime dependency (#1264)

`libraft-headers` has `librmm` listed as a `host` and `run` dependency in its recipe.

Since `librmm` has a `run_exports` value, this causes there to be two `librmm` runtime dependency entries in the resulting `libraft-headers` conda package, each with slightly version specifiers.

To prevent this from occurring, I've added `librmm` to the `ignore_run_exports_from` key in the `libraft-headers` recipe.

Note that another way to solve this would be to remove `librmm` from the `run` dependencies, but this is inconsistent with the rest of the RAPIDS recipes.

Authors:
  - AJ Schmidt (https://github.com/ajschmidt8)

Approvers:
  - Ray Douglass (https://github.com/raydouglass)

URL: #1264

conda/recipes/libraft/meta.yaml

@@ -37,6 +37,7 @@ outputs:
       string: cuda{{ cuda_major }}_{{ date_string }}_{{ GIT_DESCRIBE_HASH }}_{{ GIT_DESCRIBE_NUMBER }}
       ignore_run_exports_from:
         - {{ compiler('cuda') }}
+        - librmm
     requirements:
       build:
         - {{ compiler('c') }}