[Merged by Bors] - fix(scripts/runSkimmer): only lake update skimmer

[thorimur]

Previously, runSkimmer.sh would run lake update, thus potentially erroneously updating packages from mathlib in its own .lake/packages. By using lake update skimmer we ensure that only skimmer itself (which depends on nothing) is updated, and we match the mathlib dependencies to whatever mathlib already has. This ensures that we're able to use the mathlib cache.

Note: this still clones every package into scripts/SideSkimmer/.lake/packages/—but by cloning the right version, we can use the cache.

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To test this locally, check out the PR, run lake exe cache get and (assuming you get a full cache) run scripts/runSkimmer.sh. It should do a little bit of setup, then zoom through all of its jobs (successfully applying all 0 try-this suggestions). :)

[github-actions]

PR summary 65b5e1097d

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff (regex)

No declarations were harmed in the making of this PR! 🐙

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

## summary with just the declaration names:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh <optional_commit>

## more verbose report:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh long <optional_commit>

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

Declarations diff (Lean)

✅ Lean-aware diff — post-build, computed from the Lean environment (commit 65b5e10).

• +0 new declarations
• −0 removed declarations

No declaration differences.

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No changes to strong technical debt.

No changes to weak technical debt.

Current commit 65b5e1097d
Reference commit f34e762642

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/scripts/reporting/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

[github-actions]

✅ PR Title Formatted Correctly

The title of this PR has been updated to match our commit style conventions.
Thank you!

[grunweg]

Thanks! I'll trust that you caught all the places to fix (and in any case, this seems like an improvement even if missing one), so:
bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• ci (staging) / Build
• ci (staging) / Test and lint
• ci (staging) / Post-Build Step
• ci (staging) / Lint style
• ci (staging) / Post-CI job