Add OpenSSF Scorecard badge (#1121)

README.md

@@ -1,6 +1,7 @@
 # Receptor
 
-[![codecov](https://codecov.io/gh/ansible/receptor/branch/devel/graph/badge.svg?token=RAW5Bvh3hM)](https://codecov.io/gh/ansible/receptor)
+[![codecov](https://codecov.io/gh/ansible/receptor/branch/devel/graph/badge.svg?token=RAW5Bvh3hM)](https://codecov.io/gh/ansible/receptor)[![OpenSSF
+Scorecard](https://api.securityscorecards.dev/projects/github.com/ansible/receptor/badge)](https://api.securityscorecards.dev/projects/github.com/ansible/receptor)
 
 Receptor is an overlay network intended to ease the distribution of work across a large and dispersed collection of workers.  Receptor nodes establish peer-to-peer connections with each other via existing networks.  Once connected, the Receptor mesh provides datagram (UDP-like) and stream (TCP-like) capabilities to applications, as well as robust unit-of-work handling with resiliency against transient network failures.