sagemathgh-35050: Add missing commit when building large Cremona data…

…base

    
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### 📚 Description

Building the large Cremona database fails like this on an x86_64 Fedora
Rawhide machine.  (I captured the output from an old sagemath 9.6 build,
but the same error occurs with sagemath 9.7.)
```
Inserting allgens.90000-99999
Committing...
Traceback (most recent call last):
  File "/builddir/build/BUILD/sage-9.6/cremona.sage.py", line 10, in
<module>
    c._init_from_ftpdata('ecdata-2019-10-29')
  File "/builddir/build/BUILDROOT/sagemath-9.6-
4.fc38.x86_64/usr/lib64/python3.11/site-
packages/sage/databases/cremona.py", line 1397, in _init_from_ftpdata
    self.vacuum()
  File "/builddir/build/BUILDROOT/sagemath-9.6-
4.fc38.x86_64/usr/lib64/python3.11/site-
packages/sage/databases/sql_db.py", line 2180, in vacuum
    self.__connection__.execute('VACUUM')
sqlite3.OperationalError: cannot VACUUM from within a transaction
```
The issue is a missing database commit, which this PR adds.

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URL: sagemath#35050
Reported by: Jerry James
Reviewer(s): Vincent Macri

src/sage/databases/cremona.py

@@ -1643,6 +1643,7 @@ def _init_allgens(self, ftpdata, largest_conductor=0):
             con.executemany("UPDATE t_curve SET gens=? WHERE curve=?",
                 curve_data)
             print("Committing...")
+            self.commit()
             if largest_conductor and int(v[0]) > largest_conductor:
                 break