Update Rust crate adw to 0.8.0

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
adw (source)	dependencies	minor	0.6.0 → 0.8.0

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Configuration

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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 libadwaita@0.6.0 --precise 0.8.1
    Updating crates.io index
error: failed to select a version for `gtk4-sys`.
    ... required by package `gtk4 v0.8.2`
    ... which satisfies dependency `gtk4 = "^0.8.2"` of package `vector-browser v0.1.0 (/tmp/renovate/repos/github/3webs-org/vector)`
versions that meet the requirements `^0.8` are: 0.8.2, 0.8.1, 0.8.0

package `gtk4-sys` links to the native library `gtk-4`, but it conflicts with a previous package which links to `gtk-4` as well:
package `gtk4-sys v0.10.0`
    ... which satisfies dependency `gtk-sys = "^0.10"` of package `libadwaita-sys v0.8.0`
    ... which satisfies dependency `ffi = "^0.8"` of package `libadwaita v0.8.0`
    ... which satisfies dependency `adw = "^0.8.0"` of package `vector-browser v0.1.0 (/tmp/renovate/repos/github/3webs-org/vector)`
Only one package in the dependency graph may specify the same links value. This helps ensure that only one copy of a native library is linked in the final binary. Try to adjust your dependencies so that only one package uses the `links = "gtk-4"` value. For more information, see https://doc.rust-lang.org/cargo/reference/resolver.html#links.

failed to select a version for `gtk4-sys` which could resolve this conflict