Bug: [REFACTOR] add `requires_cvv` config while creating merchant account



### Feature Description

Insert requires_cvv config during merchant account creation itself. while getting that config during list_customer_payment_method, if not found in db, we insert it into db.

### Possible Implementation

in order to reduce db call in during listing payment methods, we insert config for requires_cvv during merchant creation itself

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

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

### Have you read the Contributing Guidelines?

- [X] I have read the [Contributing Guidelines](https://github.com/juspay/hyperswitch/blob/main/docs/CONTRIBUTING.md)

### Are you willing to submit a PR?

Yes, I am willing to submit a PR!
diff --git a/crates/router/src/core/admin.rs b/crates/router/src/core/admin.rs
index dabe22da626..c7009bf4cc9 100644
--- a/crates/router/src/core/admin.rs
+++ b/crates/router/src/core/admin.rs
@@ -219,6 +219,17 @@ pub async fn create_merchant_account(
         .insert_merchant(merchant_account, &key_store)
         .await
         .to_duplicate_response(errors::ApiErrorResponse::DuplicateMerchantAccount)?;
+
+    db.insert_config(diesel_models::configs::ConfigNew {
+        key: format!("{}_requires_cvv", merchant_account.merchant_id),
+        config: "true".to_string(),
+    })
+    .await
+    .map_err(|err| {
+        crate::logger::error!("Error while setting requires_cvv config: {err:?}");
+    })
+    .ok();
+
     Ok(service_api::ApplicationResponse::Json(
         merchant_account
             .try_into()
diff --git a/crates/router/src/core/payment_methods/cards.rs b/crates/router/src/core/payment_methods/cards.rs
index c22b7323095..20a3e130eb2 100644
--- a/crates/router/src/core/payment_methods/cards.rs
+++ b/crates/router/src/core/payment_methods/cards.rs
@@ -1831,7 +1831,7 @@ pub async fn list_customer_payment_method(
         )
         .await
         .change_context(errors::ApiErrorResponse::InternalServerError)
-        .attach_printable("Failed to fetch merchant_id config for requires_cvv")?;
+        .attach_printable("Failed to fetch requires_cvv config")?;
 
     let requires_cvv = is_requires_cvv.config != "false";
 

## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [ ] Bugfix
- [ ] New feature
- [ ] Enhancement
- [x] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
<!-- Describe your changes in detail -->
This PR includes changes for inserting requires_cvv config during merchant account creation itself. while getting that config during `list_customer_payment_method`, if not found in db, we insert it into db.

### Additional Changes

- [ ] This PR modifies the API contract
- [ ] This PR modifies the database schema
- [ ] This PR modifies application configuration/environment variables

<!--
Provide links to the files with corresponding changes.

Following are the paths where you can find config files:
1. `config`
2. `crates/router/src/configs`
3. `loadtest/config`
-->


## Motivation and Context
<!--
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If it fixes an open issue, please link to the issue here.

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can focus on the implementation (unless it is an obvious bug or documentation fix
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## How did you test it?
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![image](https://github.com/juspay/hyperswitch/assets/70657455/5daec1a0-4a85-4896-b183-86fb585e0a0d)


## Checklist
<!-- Put an `x` in the boxes that apply -->

- [x] I formatted the code `cargo +nightly fmt --all`
- [x] I addressed lints thrown by `cargo clippy`
- [x] I reviewed the submitted code
- [ ] I added unit tests for my changes where possible
- [ ] I added a [CHANGELOG](/CHANGELOG.md) entry if applicable
