Thanks to this, we will upgrade external repos to proper versions, instead of always upgrading them to versions set in pkg files from master branches of non-external repos.
I.e. if mynewt-core will be upgraded to version 1.11.0, external repos included in mynewt-core pkg.yml files are going be downloaded and upgraded as specified
in those files from mynewt_1_11_0_tag. Without this external repos included in mynewt-core would be upgraded to versions specified in pkgs from mynewt-core's
master branch, which would lead to versions mismatch and probably compilation errors
Thanks to this, we will upgrade external repos to proper versions, instead of always upgrading them to versions set in pkg files from master branches of non-external repos.
I.e. if mynewt-core will be upgraded to version 1.11.0, external repos included in mynewt-core pkg.yml files are going be downloaded and upgraded as specified in those files from mynewt_1_11_0_tag. Without this external repos included in mynewt-core would be upgraded to versions specified in pkgs from mynewt-core's master branch, which would lead to versions mismatch and probably compilation errors