docs: migrate to v8.0.0

Signed-off-by: Jan Kowalleck <[email protected]>

Author: jkowalleck

docs/upgrading.rst

@@ -42,8 +42,8 @@ Old: ``my_bom.metadata.tools.add(my_tool)``
 
 New: ``my_bom.metadata.tools.tools.add(my_tool)``
 
-Altering Metadata Tools
------------------------
+Altering Vulnerability Tools
+----------------------------
 
 Property :attr:`cyclonedx.model.vulnerability.Vulnerability.tools` is an instance of :class:`cyclonedx.model.tool.ToolsRepository`, now.
 Therefore, the process of adding new tools was changed.