env_changes from component not forgotten for setup

[JanStreffing]

While working on https://github.com/esm-tools/esm_tools/tree/feat/awicm3-v3.3 I found, that the new switch in rnfmap:

esm_tools/configs/components/rnfmap/rnfmap.yaml

Line 200 in 4076f45

iolibraries: system_gnu_libs

is not ignored in a compile for rnfmap for awicm3-v3.2:

In 'oifs':

iolibraries: system_libs

iolibraries: system_gnu_libs

Environment variable 'iolibraries' defined in 'oifs' is going to be overwritten by the one defined in 'rnfmap'. Are you okay with that? (Y/n): Y

Environment conflict
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Intended design is, that the env changes in the component rnfmap.yaml should be forgotten for the setup awicm3. Only rnfmap env changes from the rnfmap.env.yaml, which is specifically included in the setup awicm3, should be applied.