feat: Add mimetype detection for rich text format (rtf) (#886)

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Signed-off-by: Michael Schlenker <michael.schlenker@contact-software.com>
Signed-off-by: Jan Kowalleck <jan.kowalleck@gmail.com>
Co-authored-by: Michael Schlenker <michael.schlenker@contact-software.com>
Co-authored-by: Jan Kowalleck <jan.kowalleck@gmail.com>

Author: 3 people

cyclonedx_py/_internal/utils/mimetypes.py

@@ -29,6 +29,7 @@
     '.md': 'text/markdown',
     '.txt': 'text/plain',
     '.rst': 'text/prs.fallenstein.rst',
+    '.rtf': 'application/rtf',
     '.xml': 'text/xml',  # not `application/xml` -- our scope is text!
     # license-specific files
     '.license': _MIME_TEXT_PLAIN,