Implement `reset_index_checkpoint` and `reset_source_checkpoint` metastore APIs and CLI commands

[guilload]

Description

Per title.

How was this PR tested?

• added unit test
• ran make test-all command

[guilload]

As discussed offline with @fulmicoton, we currently don't have a pressing need for this API. We will revisit when necessary.

[guilload]

Reopened. See #1631.

[guilload]

This PR is ready for review.

I have introduced two new metastore APIs, which completely clears the checkpoints (keys are removed)

• reset_index_checkpoint(index_id)
• reset_source_checkpoint(index_id, source_id)

I have introduced two new CLI commands:

• index reset-checkpoint --index <index ID>
• source reset-checkpoint --index <index ID> --source <source ID>

[guilload]

PTAL!

[kstaken]

FYI, in relation to this as part of the Kafka offset storage I've been working on metastore level changes to move checkpoints into a separate table on Postgres backed metastores. As part of that I'm adding two APIs, one of which would overlap with this.

    /// Retrieves the current checkpoints for an index
    ///
    /// Returns a `IndexCheckpoint` for the provided `index_id` and optionally filtered by
    /// `source_id`, `resource` and `group_id`.
    /// If no checkpoint has been stored yet the result will be an empty `IndexCheckpoint`.
    async fn index_checkpoint(
        &self,
        index_id: &str,
        source_id: Option<String>,
        resource: Option<String>,
        group_id: Option<String>,
    ) -> MetastoreResult<IndexCheckpoint>;

    /// Removes the current checkpoints for an index
    ///
    /// Removes all checkpoints that match the provided `index_id` and optionally filtered by
    /// `source_id`, `resource` and `group_id`.
    /// If no checkpoint has been stored it will not be considered an error.
    async fn delete_index_checkpoint(
        &self,
        index_id: &str,
        source_id: Option<String>,
        resource: Option<String>,
        group_id: Option<String>,
    ) -> MetastoreResult<()>;