Update README.md

Author: userdocs

README.md

@@ -47,7 +47,7 @@ To used the image dynamically
 docker run -it ghcr.io/userdocs/iperf3-static:latest iperf3 --version
 ```
 
-### Alpine multiarch info
+## Alpine multiarch info
 
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@@ -65,7 +65,7 @@ docker run -it ghcr.io/userdocs/iperf3-static:latest iperf3 --version
 
 </details>
 
-### Windows x86_64 info
+## Windows x86_64 info
 
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@@ -76,7 +76,7 @@ https://github.com/userdocs/iperf3-static/blob/master/cygwin-installer.cmd
 
 </details>
 
-### Generic Build dependencies
+## Generic Build dependencies
 
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