[mongo] MongoDB 8.0 breaks WiredTiger ticket metrics - wiredTiger.concurrentTransactions renamed to queues.execution

[cshaworth]

MongoDB 8.0 renamed serverStatus().wiredTiger.concurrentTransactions to serverStatus().queues.execution (see MongoDB 8.0 compatibility docs).

The current integration still reads from the old path, so the following metrics are missing on MongoDB 8.0+ instances:

mongodb.wiredtiger.concurrenttransactions.read.available
mongodb.wiredtiger.concurrenttransactions.read.out
mongodb.wiredtiger.concurrenttransactions.read.totaltickets
mongodb.wiredtiger.concurrenttransactions.write.available
mongodb.wiredtiger.concurrenttransactions.write.out
mongodb.wiredtiger.concurrenttransactions.write.totaltickets

Expected: Integration should check both paths for backwards compatibility with 7.x and forward compatibility with 8.0+
MongoDB versions affected: 8.0+