sagemathgh-39551: Correct an error message.

    
* src/sage/sat/solvers/dimacs.py: The particle "not" makes all the
difference.

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The patch should be self-explaining. When trying to run a SAT solver
that is not available, I get an error message such as
Could run 'kissat -q /tmp/tmp0r4t8342/tmp_j1161zu3', perhaps you need to
add your SAT solver to $PATH?
Clearly there is a "not" missing.


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preview.

### ⌛ Dependencies

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URL: sagemath#39551
Reported by: AndreasEnge
Reviewer(s): Travis Scrimshaw

src/sage/sat/solvers/dimacs.py

@@ -425,7 +425,7 @@ def _run(self):
         try:
             process = subprocess.Popen(args, stdout=subprocess.PIPE)
         except OSError:
-            raise OSError("Could run '%s', perhaps you need to add your SAT solver to $PATH?" % (" ".join(args)))
+            raise OSError("Could not run '%s', perhaps you need to add your SAT solver to $PATH?" % (" ".join(args)))
 
         try:
             while process.poll() is None: