Suggest mutable borrow on read only for-loop that should be mutable

[estebank]

error[E0596]: cannot borrow `*test` as mutable, as it is behind a `&` reference
  --> $DIR/suggest-mut-iterator.rs:22:9
   |
LL |     for test in &tests {
   |                 ------ this iterator yields `&` references
LL |         test.add(2);
   |         ^^^^ `test` is a `&` reference, so the data it refers to cannot be borrowed as mutable
   |
help: use a mutable iterator instead
   |
LL |     for test in &mut tests {
   |                  +++

Fix #114311.

[rustbot]

r? @davidtwco

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[davidtwco]

@bors r+

[bors]

📌 Commit c1a7af0 has been approved by davidtwco

It is now in the queue for this repository.

[bors]

⌛ Testing commit c1a7af0 with merge aa5dbee...

[bors]

☀️ Test successful - checks-actions
Approved by: davidtwco
Pushing aa5dbee to master...

[rust-timer]

Finished benchmarking commit (aa5dbee): comparison URL.

Overall result: ❌✅ regressions and improvements - no action needed

@rustbot label: -perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	0.4%	[0.4%, 0.4%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.3%	[-0.3%, -0.3%]	2
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	1.0%	[0.8%, 1.3%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-1.7%	[-3.4%, -0.7%]	4
All ❌✅ (primary)	-	-	0

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 630.163s -> 630.156s (-0.00%)
Artifact size: 315.81 MiB -> 315.55 MiB (-0.08%)