fix: flag trends should support bigint for yes and no evaluations (#6930)

Recently we see some pods failing with inserting yes, no values that
were over int. Increasing type to bigint.

src/migrations/20240425132155-flag-trends-bigint.js

@@ -0,0 +1,14 @@
+exports.up = function (db, cb) {
+    db.runSql(`
+        ALTER TABLE flag_trends ALTER COLUMN total_yes TYPE bigint;
+        ALTER TABLE flag_trends ALTER COLUMN total_no TYPE bigint;
+    `, cb);
+};
+
+exports.down = function (db, cb) {
+    db.runSql(
+        `
+        `,
+        cb,
+    );
+};