Original sed code does not work on BSD sed with BRE

src/_fvm

@@ -36,7 +36,7 @@
 
 _fvm_versions() {
   local -a versions
-  versions=($(fvm releases | grep -E '[0-9]+\.[0-9]+.[0-9]+' | sed -e 's/^.* \(v\?[0-9][0-9]*\.[^ ]*\).*$/\1/g'))
+  versions=($(fvm releases | awk '/[0-9]+\.[0-9]+\.[0-9]+/{ sub(/^[^│]*│ /, ""); print $1}'))
   versions=(master beta stable $versions)
   _describe 'versions' versions
 }