Simplify conan_build_info --v2 arguments

[czoido]

Changelog: Bugfix: Removing --skip-env and --multi-module arguments for conan_build_info --v2. Now the environment is not captured (will be handled by the Artifactory plugin) and recipes and packages are saved as different modules in build info.
Docs: conan-io/docs#1486

This PR simplifies Conan build info creation by always saving the information in different modules for recipes and packages (removes the old --multi-module argument). Also, it will not capture environment information by default (removes the old --skip-env argument because the environment information will be handled by the Jenkins Artifactory plugin once this command is integrated into the plugin).

Closes #6144 by removing the arguments.

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