Adapting to lua pattern matching for minified downloads

src/spm/spm.lua

@@ -431,7 +431,7 @@ local function installPackage(requestedPackage, installPath, doUpdate)
         end
 
         if packageInfo.minified or options.m then
-            filePath = string.gsub(filePath, "(.+)\\.(.+)$", "%1\\.min\\.%2")
+            filePath = string.gsub(filePath, "(.+)%.lua$", "%1") .. ".min.lua"
         end
 
         local success = pcall(downloadFile, repositoryPath .. "/" .. filePath, installedPath)