undo bump to non-existent abseil-cpp

[h-vetinari]

We dropped the old name of the abseil library in conda-forge/abseil-cpp-feedstock#53, but the bot still bumped the output for some reason.

I'm not sure what the policy is for outputs that aren't active anymore, but I guess it doesn't hurt to keep them in the global pinning for a while longer, to ensure that people using the old output (e.g. in an old feedstock branch) still get something when rerendering.

CC @conda-forge/abseil-cpp

[conda-forge-webservices]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.