Bump debian-inspector version

Scancode version 21.6.7 which fixes some CLI invocation errors
is compatible with debian-inspector version 21.5.25. Hence we
bump tern's requirements to that version.

Signed-off-by: Nisha K <[email protected]>

Author: Nisha K

requirements.txt

@@ -12,7 +12,7 @@ dockerfile-parse~=1.1
 requests~=2.25
 stevedore>=3.3
 pbr>=5.6
-debian-inspector>=0.9
+debian-inspector>=21.5
 regex>=2021.4
 GitPython~=3.1
 prettytable~=2.1