Accept only AssertionEngine == 0.6.1

Fixes #2525

Author: aaltat

Browser/requirements.txt

@@ -4,7 +4,7 @@ grpcio-tools == 1.51.1
 protobuf==4.21.12
 robotframework >=4.1.3
 robotframework-pythonlibcore >= 4.0.0
-robotframework-assertion-engine >= 0.6.1
+robotframework-assertion-engine == 0.6.1
 typing-extensions >= 4.4.0
 wrapt >= 1.14.1
 overrides >= 7.3.1