Only allow compiletest to use feature(test), not any other feature

[jyn514]

Using language features occasionally causes issues when using nightly to bootstrap, rather than beta.
See #59264 for additional context.

[rust-highfive]

r? @Mark-Simulacrum

(rust-highfive has picked a reviewer for you, use r? to override)

[Mark-Simulacrum]

@bors r+ rollup=iffy

[bors]

📌 Commit e71c48c has been approved by Mark-Simulacrum

[bors]

⌛ Testing commit e71c48c with merge 372a985d9db50f8b0134b258d9af4c133316ce82...

[bors]

💔 Test failed - checks-actions

[jyn514]

Looks spurious.

/checkout/src/test/rustdoc-gui/search-tab-change-title-fn-sig.goml search-tab-change-title-fn-sig... FAILED
Error:  (line 6) Error: The following CSS selector "#titles" was not found: for command `wait-for: "#titles"`

[rust-log-analyzer]

The job x86_64-gnu-tools failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

.......... (60/64)
...       (64/64)


/checkout/src/test/rustdoc-gui/search-tab-change-title-fn-sig.goml search-tab-change-title-fn-sig... FAILED
[ERROR] (line 6) Error: The following CSS selector "#titles" was not found: for command `wait-for: "#titles"`
Build completed unsuccessfully in 0:00:46

[jackh726]

@bors retry

[bors]

⌛ Testing commit e71c48c with merge 8bf9c20...

[bors]

☀️ Test successful - checks-actions
Approved by: Mark-Simulacrum
Pushing 8bf9c20 to master...

[rust-timer]

Finished benchmarking commit (8bf9c20): comparison url.

Instruction count

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

Max RSS (memory usage)

Results

• Primary benchmarks: mixed results
• Secondary benchmarks: 🎉 relevant improvement found

	mean1	max	count2
Regressions 😿 (primary)	3.9%	3.9%	1
Regressions 😿 (secondary)	N/A	N/A	0
Improvements 🎉 (primary)	-6.0%	-6.0%	1
Improvements 🎉 (secondary)	-2.2%	-2.2%	1
All 😿🎉 (primary)	-1.0%	-6.0%	2

Cycles

Results

• Primary benchmarks: no relevant changes found
• Secondary benchmarks: 😿 relevant regression found

	mean1	max	count2
Regressions 😿 (primary)	N/A	N/A	0
Regressions 😿 (secondary)	2.1%	2.1%	1
Improvements 🎉 (primary)	N/A	N/A	0
Improvements 🎉 (secondary)	N/A	N/A	0
All 😿🎉 (primary)	N/A	N/A	0

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

@rustbot label: -perf-regression

Footnotes

1. the arithmetic mean of the percent change ↩ ↩²

2. number of relevant changes ↩ ↩²