fix: "or-later" suffix updated to consider deprecated "+" operator (#1907)

* fix: or-later suffix has been updated to consider deprecated +

If a given license has the suffix "or-later" it previously could have
been considered or represented with a "+". Example "GFDL-1.0-or-later"
could have been represented as "GFDL-1.0+". This PR allows the license
list generation to consider "or-later" as == to "+" when generating
permutations for upgrading deprecated licenses.

---------

Signed-off-by: Christopher Phillips <christopher.phillips@anchore.com>

internal/spdxlicense/license_list_test.go

@@ -12,5 +12,6 @@ func TestLicenceListIDs(t *testing.T) {
 	assert.Equal(t, "ZPL-2.1", licenseIDs["zpl2.1"])
 	assert.Equal(t, "GPL-2.0-only", licenseIDs["gpl2"])
 	assert.Equal(t, "GPL-2.0-or-later", licenseIDs["gpl2+"])
+	assert.Equal(t, "GFDL-1.2-or-later", licenseIDs["gfdl1.2+"])
 	assert.NotEmpty(t, Version)
 }