Fix license in metainfo

[Ayush1325]

• Use SPDX license name

Sanity check:

• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Code changes

(Delete or ignore this section for documentation changes)

• Are you doing the PR on the next branch?

If the change is a new feature or adding to/changing an existing one:

• Have you created/updated the relevant documentation page(s)?

[Keats]

ah sorry can i'll do it in master instead otherwise its going to be hanging in there for a while