Update C++ badge in README.md

Change-Id: I776fbdf1438b68ef8eb35ab00fa0015209b89c9c
diff --git a/README.md b/README.md
index 8f027ad..66e8fb9 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 [![CI](https://github.com/named-data/ChronoSync/actions/workflows/ci.yml/badge.svg)](https://github.com/named-data/ChronoSync/actions/workflows/ci.yml)
 [![Docs](https://github.com/named-data/ChronoSync/actions/workflows/docs.yml/badge.svg)](https://github.com/named-data/ChronoSync/actions/workflows/docs.yml)
-![Language](https://img.shields.io/badge/C%2B%2B-14-blue)
+![Language](https://img.shields.io/badge/C%2B%2B-17-blue)
 ![Latest version](https://img.shields.io/github/v/tag/named-data/ChronoSync?label=Latest%20version)
 
 > DEPRECATION NOTICE: ChronoSync's design is outdated. We recommend using more recent sync protocols, such as [PSync](https://named-data.net/doc/PSync/current/index.html) or [StateVectorSync](https://named-data.github.io/StateVectorSync/).