Solver: CommandLine: Try fix Windows encoding crash.

src/Solver/CommandLine.py

@@ -167,8 +167,10 @@ class CommandLineSolver(AbstractSolver):
             repertory, "pamhyr-study-description.txt"
         )
 
-        with open(path, "w+") as f:
-            txt = study.description
+        with open(path, "w+", encoding='utf-8') as f:
+            txt = study.description\
+                       .encode()\
+                       .decode('utf-8', 'replace')
             f.write(txt)
 
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