Fix tidy check if book submodule is not checked out

[ehuss]

This fixes tidy in a checkout without submodules. #127786 added a new cargo workspace, and the corresponding checks in tidy. There is code in tidy to skip those checks if the submodule is checked out, but that code assumed the root of the workspace was also the root of the submodule. With rustbook, the root is src/tools/rustbook, but the submodules it needs are in the src/doc directory.

The solution here is to explicitly list which submodules are needed instead of assuming the root is also the submodule.

[rustbot]

r? @Kobzol

rustbot has assigned @Kobzol.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

[rustbot]

The list of allowed third-party dependencies may have been modified! You must ensure that any new dependencies have compatible licenses before merging.

cc @davidtwco, @wesleywiser

[Mark-Simulacrum]

@bors r+ p=1

[bors]

📌 Commit e8ef886 has been approved by Mark-Simulacrum

It is now in the queue for this repository.

[bors]

⌛ Testing commit e8ef886 with merge 42103d6...

[bors]

☀️ Test successful - checks-actions
Approved by: Mark-Simulacrum
Pushing 42103d6 to master...

[rust-timer]

Finished benchmarking commit (42103d6): 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)	7.0%	[7.0%, 7.0%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-1.9%	[-1.9%, -1.9%]	1
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (primary 2.8%)

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)	2.8%	[2.8%, 2.8%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	2.8%	[2.8%, 2.8%]	1

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: 770.721s -> 770.026s (-0.09%)
Artifact size: 328.91 MiB -> 328.88 MiB (-0.01%)