Refactor variable declarations in Build function for clarity (#54)

- Changed slice initializations from shorthand to explicit var declarations for clientOpts, exportsWithOutput, and platformStrings.
- This improves readability and maintains consistency in the code style.

Author: kasugamirai

pkg/build/build.go

@@ -44,7 +44,7 @@ func Build(ctx context.Context, opts *BOpts) error {
 			grpc.MaxCallSendMsgSize(512<<20), // 512MB
 		),
 	}
-	clientOpts := []client.ClientOpt{}
+	var clientOpts []client.ClientOpt
 	for _, opt := range grpcOpts {
 		clientOpts = append(clientOpts, client.WithGRPCDialOption(opt))
 	}
@@ -86,7 +86,7 @@ func Build(ctx context.Context, opts *BOpts) error {
 		dest: outputPath,
 	}
 
-	exportsWithOutput := []client.ExportEntry{}
+	var exportsWithOutput []client.ExportEntry
 	for _, export := range exports {
 		switch export.Type {
 		case client.ExporterLocal:
@@ -142,7 +142,7 @@ func Build(ctx context.Context, opts *BOpts) error {
 		solveOpt.FrontendAttrs["build-arg:"+k] = v
 	}
 
-	platformStrings := []string{}
+	var platformStrings []string
 	for _, platform := range opts.Platforms {
 		platformStrings = append(platformStrings, platforms.Format(platforms.Normalize(platform)))
 	}