docs: add fossa badge to readme

Signed-off-by: Abhinandan Purkait <[email protected]>

Author: Abhinandan-Purkait

README.md

@@ -1,2 +1,5 @@
 # CAS dependencies
 Common set of dependencies used by both control-plane and data-plane components.
+
+# License
+[![FOSSA Status](https://app.fossa.com/api/projects/custom%2B39852%2Fgit%40github.com%3Aopenebs%2Fmayastor-dependencies.git.svg?type=shield&issueType=license)](https://app.fossa.com/projects/custom%2B39852%2Fgit%40github.com%3Aopenebs%2Fmayastor-dependencies.git?ref=badge_shield&issueType=license)