Update: Rename license files to use word characters and avoid dashes.

This makes the licenses file names friendlier and easier to work with.
This also better allows for combining licenses where a word character, such as a minus sign `-`, can be used to designate the different parts.

diff --git a/licenses/cc-by-sa-4.0 b/licenses/cc_by_sa_4_0
similarity index 100%
rename from licenses/cc-by-sa-4.0
rename to licenses/cc_by_sa_4_0

diff --git a/licenses/clarified-1.0-or-later b/licenses/clarified_1_0_or_later
similarity index 100%
rename from licenses/clarified-1.0-or-later
rename to licenses/clarified_1_0_or_later

diff --git a/licenses/lgpl-2.1-or-later b/licenses/lgpl_2_1_or_later
similarity index 100%
rename from licenses/lgpl-2.1-or-later
rename to licenses/lgpl_2_1_or_later

diff --git a/licenses/open-standard-license-1.1-or-later b/licenses/open_standard_license_1_1_or_later
similarity index 100%
rename from licenses/open-standard-license-1.1-or-later
rename to licenses/open_standard_license_1_1_or_later