Update Rust crate dirs to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
dirs	dependencies	major	5.0.1 → 6.0.0

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Configuration

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🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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[renovate]

⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
• you click the rebase/retry checkbox if found above, or
• you rename this PR's title to start with "rebase!" to trigger it manually

The artifact failure details are included below:

File name: Cargo.lock

Command failed: cargo update --config net.git-fetch-with-cli=true --manifest-path Cargo.toml --package dirs@5.0.1 --precise 6.0.0
    Updating crates.io index
error: failed to select a version for `reqwest`.
    ... required by package `dsc v0.12.0-pre (/tmp/renovate/repos/github/docspell/dsc)`
versions that meet the requirements `^0.13.0` are: 0.13.1, 0.13.0

package `dsc` depends on `reqwest` with feature `rustls-tls` but `reqwest` does not have that feature.


failed to select a version for `reqwest` which could resolve this conflict