Update README.md to dso.mil
Removed instances of dsop.io and replaced with dso.mil.
UNCLASSIFIED - NO CUI
Currently supported Big Bang Version is 2.42.0
ATTENTION: Immediate action is required to maintain compatibility with P1 services. Please visit https://p1notifications.dso.mil and see the "DSO.MIL Certificates Renewal" announcement under the "Notifications" section for more details.
Removed instances of dsop.io and replaced with dso.mil.
UNCLASSIFIED - NO CUI