Update dependency ovos-plugin-manager to v2 (#14)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

requirements.txt

@@ -1,4 +1,4 @@
 torchaudio
 speechbrain~=1.0.0
-ovos-plugin-manager~=0.0, >=0.0.26a15
+ovos-plugin-manager~=2.1, >=2.1
 ovos-config>=0.0.12