feat: change token key to match normal actions format

[drazisil]

Warning: Unexpected input(s) 'CODECOV_TOKEN', valid inputs are ['token', 'files', 'directory', 'flags', 'aws_curl_args', 'codecov_curl_args', 'commit_parent', 'env_vars', 'fail_ci_if_error', 'file', 'functionalities', 'gcov_args', 'gcov_executable', 'gcov_path_exclude', 'gcov_path_include', 'gcov_prefix', 'gcov_root_dir', 'move_coverage_to_trash', 'name', 'override_branch', 'override_build', 'override_commit', 'override_pr', 'override_tag', 'path_to_write_report', 'root_dir', 'verbose', 'working-directory', 'xcode_derived_data', 'xcode_package']

I tried using `CODECOV_TOKEN like it is suggested by GitHub to use other secrets https://github.com/drazisil/scaling_umbrella/actions/runs/919695618/workflow#L45

Is it possible to add GITHUB_TOKEN as an alias to token?