Manually bump version to 6.12.0

[traversaro]

Automatic PRs to bump the version are currently not working, see https://github.com/conda-forge/libignition-gazebo-feedstock/issues/24 .

Checklist

• [x] Used a personal fork of the feedstock to propose changes
• [x] Bumped the build number (if the version is unchanged)
• [ ] Reset the build number to 0 (if the version changed)
• [x] Re-rendered with the latest conda-smithy (Use the phrase code>@<space/conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• [x] Ensured the license file is being packaged.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-webservice.

It appears you are making a pull request from a branch in your feedstock and not a fork. This procedure will generate a separate build for each push to the branch and is thus not allowed. See our documentation for more details.

Please close this pull request and remake it from a fork of this feedstock.

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[conda-forge-linter]

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.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-webservice.

It appears you are making a pull request from a branch in your feedstock and not a fork. This procedure will generate a separate build for each push to the branch and is thus not allowed. See our documentation for more details.

Please close this pull request and remake it from a fork of this feedstock.

Have a great day!

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-webservice.

It appears you are making a pull request from a branch in your feedstock and not a fork. This procedure will generate a separate build for each push to the branch and is thus not allowed. See our documentation for more details.

Please close this pull request and remake it from a fork of this feedstock.

Have a great day!

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-webservice.

It appears you are making a pull request from a branch in your feedstock and not a fork. This procedure will generate a separate build for each push to the branch and is thus not allowed. See our documentation for more details.

Please close this pull request and remake it from a fork of this feedstock.

Have a great day!

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-webservice.

It appears you are making a pull request from a branch in your feedstock and not a fork. This procedure will generate a separate build for each push to the branch and is thus not allowed. See our documentation for more details.

Please close this pull request and remake it from a fork of this feedstock.

Have a great day!