Add the WTFPL license to common licenses
https://spdx.org/licenses/WTFPL.html
Example of package licensed under WTFPL: https://gitlab.archlinux.org/archlinux/packaging/packages/ly/-/blob/main/PKGBUILD?ref_type=heads#L11
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https://spdx.org/licenses/WTFPL.html
Example of package licensed under WTFPL: https://gitlab.archlinux.org/archlinux/packaging/packages/ly/-/blob/main/PKGBUILD?ref_type=heads#L11