fix(deps): update rust crate schemars to 0.9

[elastic-renovate-prod]

This PR contains the following updates:

Package	Type	Update	Change
schemars (source)	dependencies	minor	0.8 -> 0.9

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Release Notes

GREsau/schemars (schemars)

v0.9.0

Compare Source

This version is identical to 1.0.0-alpha.18, but is available for those who are unable to unwilling to use a pre-release version.

Those upgrading from Schemars 0.8 may want to consult the migration guide, which also applies when migrating from 0.8 to 0.9.

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Configuration

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

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This PR has been generated by Renovate Bot.

[elastic-renovate-prod]

⚠️ 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 --workspace
    Updating crates.io index
    Updating git repository `https://github.com/elastic/elasticsearch-rs`
From https://github.com/elastic/elasticsearch-rs
 * [new ref]         8eb4e7fc98046882de46536b3a25291511e2ca75 -> refs/commit/8eb4e7fc98046882de46536b3a25291511e2ca75
error: failed to select a version for `schemars`.
    ... required by package `elasticsearch-core-mcp-server v0.4.6 (/tmp/renovate/repos/github/elastic/mcp-server-elasticsearch)`
versions that meet the requirements `^0.9` (locked to 0.9.0) are: 0.9.0

package `elasticsearch-core-mcp-server` depends on `schemars` with feature `chrono` but `schemars` does not have that feature.
 package `schemars` does have feature `chrono04`


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