[BUG]: MCA metadata deserialization failures should be 4xx

[swangi-kumari]

:memo: Feature Description

• We don't have validation for Merchant Connector Account metadata, So while creating MCA we are allowing any json value. Because of which RequestEncodingFailure happening during payments for the MCA which doesn't have the expected fields.
• Recreating scenario : Create a merchant connector account for coinbase with empty metadata .It doesn't throw error as we don't have metadata validation for coinbase . If you try to make payment now this will throw deserilization error for CoinbaseConnectorMeta which is merchant connector metadata for coinbase .

:hammer: Possible Implementation

• In the event of a deserialization failure of MCA metadata during payments and refunds, convert the ParsingFailed error to ConnectorError::InvalidConnectorConfig.
• We already have authType validation in core/admin.rs , we need similar validation for connector metadata for coinbase .
• Make sure that the config field in ConnectorError::InvalidConnectorConfig specifies the invalid configuration name.
• Note that the ConnectorError::InvalidConnectorConfig error is already associated with HTTP 400 in the core.
• You can check this PR for further reference https://github.com/juspay/hyperswitch/pull/2746

:bookmark: Note: All the changes needed should be contained within /hyperswitch_oss/crates/router/src/connector/utils.rs

:package: Have you spent some time checking if this feature request has been raised before?

• [X] I checked and didn't find a similar issue

:package: Have you read the Contributing Guidelines?

• [X] I have read the Contributing Guidelines

:sparkles: Are you willing to submit a PR?

[bkontur]

Incidentally, I came across this issue through the This Week in Rust newsletter, so please take a look: https://github.com/juspay/hyperswitch/pull/3168

[SanchithHegde]

Sure @bkontur, I'll assign this issue to you so that nobody else picks this up.

[bkontur]

@SanchithHegde can you, please, ping/approve CI on that #3168 , that we know all pipelines are passing?

[bkontur]

@SanchithHegde just out of curiosity, do you have any estimate for reviewing? How long does PR review take here? :)

[SanchithHegde]

Hey @bkontur, we don't have many folks available due to the holidays, I expect limited activity over the next week. Apologies for the delay!