OpenVas-Scanner Adding information on missing package

When I went over the documentation, I had the issue of missing Libcurl when trying to build from cmake. According to the online documentation, Ubuntu doesn't have a direct libcurl-dev package, and using libcurl4-openssl-dev fixes the issue.

src/22.4/source-build/openvas-scanner/build.md

@@ -14,6 +14,9 @@ cmake $SOURCE_DIR/openvas-scanner-$OPENVAS_SCANNER_VERSION \
 
 make -j$(nproc)
 ```
+```{warning}
+If missing libcurl error in Ubuntu install libcurl4-openssl-dev `sudo apt install -y libcurl4-openssl-dev`
+```
 
 ```{code-block}
 :caption: Installing openvas-scanner