Fix the signature for Sqlite3Result::columnName

[stof]

Closes #11008

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Note

Low Risk
Low risk: updates only static callmap signatures, but may surface new type errors where callers assumed string instead of handling false.

Overview
Fixes Psalm’s built-in callmap signature for SQLite3Result::columnName to reflect PHP behavior by changing its return type from string to false|string across the relevant CallMap_70/71/72.php versions.

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[stof]

The changes done in dictionaries/CallMap_73.php are coming from running the bin/stubs/gen_callmap.php script.