sqlite: disable WAL mode

As shown in containers#17831, WAL mode plays a role in causing `database is locked`
errors.  Those are errors, in theory, should not happen as the DB should
busy wait.  mattn/go-sqlite3/issues/274 has some comments indicating
that the busy handler behaves differently in WAL mode which may be an
explanation to the error.

For now, let's disable WAL mode and only re-enable it when we have
clearer understanding of what's going on.  The upstream issue along with
the SQLite documentation do not give me the clear guidance that I would
need.

[NO NEW TESTS NEEDED] - flake is only reproducible in CI.

Fixes: containers#18356
Signed-off-by: Valentin Rothberg <[email protected]>

Author: vrothberg

libpod/sqlite_state.go

@@ -32,9 +32,7 @@ type SQLiteState struct {
 const (
 	// Deal with timezone automatically.
 	sqliteOptionLocation = "_loc=auto"
-	// Set the journal mode (https://www.sqlite.org/pragma.html#pragma_journal_mode).
-	sqliteOptionJournal = "&_journal=WAL"
-	// Force WAL mode to fsync after each transaction (https://www.sqlite.org/pragma.html#pragma_synchronous).
+	// Force an fsync after each transaction (https://www.sqlite.org/pragma.html#pragma_synchronous).
 	sqliteOptionSynchronous = "&_sync=FULL"
 	// Allow foreign keys (https://www.sqlite.org/pragma.html#pragma_foreign_keys).
 	sqliteOptionForeignKeys = "&_foreign_keys=1"
@@ -44,7 +42,6 @@ const (
 	// Assembled sqlite options used when opening the database.
 	sqliteOptions = "db.sql?" +
 		sqliteOptionLocation +
-		sqliteOptionJournal +
 		sqliteOptionSynchronous +
 		sqliteOptionForeignKeys +
 		sqliteOptionTXLock