fixing go.mod file - use correct module name and valid Go version. Fixed bug in fibonacci_test.go - test wasn't testing the correct method, it was calling the same one twice

cli/main.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"backoff/fibonacci"
 	"context"
 	"flag"
 	"fmt"
@@ -10,6 +9,8 @@ import (
 	"strconv"
 	"strings"
 	"time"
+
+	"code.wmdillon.com/wmdillon/backoff/fibonacci"
 )
 
 func FormatOutput(pause time.Duration, format string) string {