Add conda-smithy version to conda-forge.yml

Just as the title says, we should add the conda-smithy version to conda-forge.yml so that we can tell what version we re-rendered (or rendered) with.

[pelson]

I think we can close this one out - it is conceivable to have a version string in the feedstock that is only updated when we re-render and something other than the version number has changed. For now though - I don’t think we need to keep this one open - the commit convention gives feedstock users a reasonably good clue.

[jakirkham]

I think PR ( https://github.com/conda-forge/conda-smithy/pull/307 ) was right on the money 💰. What we should be doing is standardizing our commits whether we re-render or the bot re-renders to make it easier to see what version we re-rendered with last. After all everything outside of the recipe directory should only be changed by re-renderings.

Beyond that, other tricks like git pre-commit hooks, automated re-rendering PR ( https://github.com/conda-forge/conda-forge-webservices/issues/74 ), and so on can be used make this a trivial nearly mindless background operation.