build: modernize Go usage

This commit modernizes Go usage. This was done with:

go run golang.org/x/tools/gopls/internal/analysis/modernize/cmd/modernize@latest -fix -test ./...

Then files needed to be `go fmt`ed and a few comments needed to be
restored.

The modernizations include replacing

- if/else conditional assignment by a call to the built-in min or max functions added in go1.21
- sort.Slice(x, func(i, j int) bool) { return s[i] < s[j] } by a call to slices.Sort(s), added in go1.21
- interface{} by the 'any' type added in go1.18
- append([]T(nil), s...) by slices.Clone(s) or slices.Concat(s), added in go1.21
- loop around an m[k]=v map update by a call to one of the Collect, Copy, Clone, or Insert functions from the maps package, added in go1.21
- []byte(fmt.Sprintf...) by fmt.Appendf(nil, ...), added in go1.19
- append(s[:i], s[i+1]...) by slices.Delete(s, i, i+1), added in go1.21
- a 3-clause for i := 0; i < n; i++ {} loop by for i := range n {}, added in go1.22

backend/onedrive/onedrive.go

@@ -2532,10 +2532,7 @@ func (o *Object) uploadMultipart(ctx context.Context, in io.Reader, src fs.Objec
 	remaining := size
 	position := int64(0)
 	for remaining > 0 {
-		n := int64(o.fs.opt.ChunkSize)
-		if remaining < n {
-			n = remaining
-		}
+		n := min(remaining, int64(o.fs.opt.ChunkSize))
 		seg := readers.NewRepeatableReader(io.LimitReader(in, n))
 		fs.Debugf(o, "Uploading segment %d/%d size %d", position, size, n)
 		info, err = o.uploadFragment(ctx, uploadURL, position, size, seg, n, options...)