Move DFP Viz screenshot to LFS (#537)

Closes #489

Authors:
  - Eli Fajardo (https://github.com/efajardo-nv)

Approvers:
  - Devin Robison (https://github.com/drobison00)

URL: #537

.gitattributes

@@ -1,5 +1,6 @@
 docs/source/developer_guide/guides/img/** filter=lfs diff=lfs merge=lfs -text
 examples/data/** filter=lfs diff=lfs merge=lfs -text
+examples/digital_fingerprinting/visualization/img/** filter=lfs diff=lfs merge=lfs -text
 morpheus/_version.py export-subst
 tests/mock_triton_server/payloads/** filter=lfs diff=lfs merge=lfs -text
 tests/tests_data/** filter=lfs diff=lfs merge=lfs -text