Remove the if block since release is done

Author: danieljbruce

handwritten/bigquery/src/bigquery.ts

@@ -2858,18 +2858,6 @@ export class BigQueryTimestamp {
     } else if (typeof value === 'string') {
       if (/^\d{4}-\d{1,2}-\d{1,2}/.test(value)) {
         pd = new PreciseDate(value);
-        if (process.env.BIGQUERY_PICOSECOND_SUPPORT === 'true') {
-          if (value.match(/\.\d{10,}/) && !Number.isNaN(pd.getTime())) {
-            /*
-            TODO:
-            When https://github.com/googleapis/nodejs-precise-date/pull/302
-            is released and we have full support for picoseconds in PreciseData
-            then we can remove this if block.
-             */
-            this.value = value;
-            return;
-          }
-        }
       } else {
         const floatValue = Number.parseFloat(value);
         if (!Number.isNaN(floatValue)) {