fix: update DocFX version specification to allow minor updates

Author: DennisDyallo

.github/workflows/build.yml

@@ -89,7 +89,7 @@ jobs:
       # Build the documentation
       - name: Build docs
         run: |
-          dotnet tool install --global docfx --version 2.78.2
+          dotnet tool install --global docfx --version "2.*"
           docfx Yubico.YubiKey/src/docfx.json --logLevel warning --log Yubico.YubiKey/docs/docfx.log
 
       # Upload documentation