Add submitted circuit instances (#12)

Author: abdonrd

.github/ISSUE_TEMPLATE/submission-path-1-observable-estimations.yml

@@ -27,7 +27,9 @@ body:
       label: Circuit
       description: The problem instance this submission addresses
       options:
-        - operator_loschmidt_echo_49x2400
+        - operator_loschmidt_echo_70x1872
+        - operator_loschmidt_echo_49x648
+        - operator_loschmidt_echo_49x1296
     validations:
       required: true
 

data/observable-estimations/circuit-instances/README.md

@@ -1 +1,5 @@
 # Observable estimations circuit instances
+
+- [Operator Loschmidt Echo 70x1872](./operator_loschmidt_echo_70x1872/)
+- [Operator Loschmidt Echo 49x648](./operator_loschmidt_echo_49x648/)
+- [Operator Loschmidt Echo 49x1296](./operator_loschmidt_echo_49x1296/)