Clippy failure on master

[alamb]

Describe the bug

A new rust version has been released: https://blog.rust-lang.org/2023/07/13/Rust-1.71.0.html

Which is causing some clippy failures:

https://github.com/apache/arrow-datafusion/actions/runs/5544297249/jobs/10121748128

 Checking datafusion-execution v27.0.0 (/__w/arrow-datafusion/arrow-datafusion/datafusion/execution)
error: items were found after the testing module
    --> datafusion/sql/tests/sql_integration.rs:3421:1
     |
3421 |   #[rstest]
     |   ^--------
     |   |
     |  _in this procedural macro expansion
     | |
3422 | | #[case::select_cluster_by_unsupported(
3423 | |     "SELECT customer_name, SUM(order_total) as total_order_amount FROM orders CLUSTER BY customer_name",
3424 | |     "This feature is not implemented: CLUSTER BY"
...    |
4162 | |     }
4163 | | }
     | |_^
     |
     = help: move the items to before the testing module was defined
     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#items_after_test_module
     = note: `-D clippy::items-after-test-module` implied by `-D warnings`
     = note: this error originates in the attribute macro `rstest` (in Nightly builds, run with -Z macro-backtrace for more info)

error: could not compile `datafusion-sql` (test "sql_integration") due to previous error
warning: build failed, waiting for other jobs to finish...
error: you should consider adding a `Default` implementation for `HyperLogLog<T>`
  --> datafusion/physical-expr/src/aggregate/hyperloglog.rs:76:5
   |
76 | /     pub fn new() -> Self {
77 | |         let registers = [0; NUM_REGISTERS];
78 | |         Self::new_with_registers(registers)
79 | |     }
   | |_____^
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#new_without_default
   = note: `-D clippy::new-without-default` implied by `-D warnings`
help: try adding this
   |
71 + impl<T> Default for HyperLogLog<T> {
72 +     fn default() -> Self {
73 +         Self::new()
74 +     }
75 + }
   |

To Reproduce

No response

Expected behavior

No response

Additional context

No response