feat: replace hasura actions base URL with env variable (forbole#379)

## Description

Closes: forbole#373 

Currently hasura actions' handler URL is hard-coded as `http://localhost:3000/[actions]`.
This PR replaces `http://localhost:3000` with `{{ACTION_BASE_URL}}` in the metadata file `actions.yaml` so hasura can read the custom handler URL from environment variable while applying hasura metadata. 

Note: 
Might need to add `-e ACTION_BASE_URL="http://localhost:3000"` as example in the setup instructions. 



---

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- [ ] targeted the correct branch
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- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
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- [ ] manually tested (if applicable)

hasura/metadata/actions.yaml

@@ -5,7 +5,7 @@ actions:
 - name: action_account_balance
   definition:
     kind: synchronous
-    handler: http://localhost:3000/account_balance
+    handler: "{{ACTION_BASE_URL}}/account_balance"
     output_type: ActionBalance
     arguments:
     - name: address
@@ -23,7 +23,7 @@ actions:
 - name: action_delegation_reward
   definition:
     kind: synchronous
-    handler: http://localhost:3000/delegation_reward
+    handler: "{{ACTION_BASE_URL}}/delegation_reward"
     output_type: "[ActionDelegationReward]"
     arguments:
     - name: address
@@ -40,7 +40,7 @@ actions:
 - name: action_delegator_withdraw_address
   definition:
     kind: synchronous
-    handler: http://localhost:3000/delegator_withdraw_address
+    handler: "{{ACTION_BASE_URL}}/delegator_withdraw_address"
     output_type: ActionAddress
     arguments:
     - name: address
@@ -55,7 +55,7 @@ actions:
 - name: action_delegation
   definition:
     kind: synchronous
-    handler: http://localhost:3000/delegation
+    handler: "{{ACTION_BASE_URL}}/delegation"
     output_type: ActionDelegationResponse
     arguments:
     - name: address
@@ -78,7 +78,7 @@ actions:
 - name: action_delegation_total
   definition:
     kind: synchronous
-    handler: http://localhost:3000/delegation_total
+    handler: "{{ACTION_BASE_URL}}/delegation_total"
     output_type: ActionBalance
     arguments:
     - name: address
@@ -95,7 +95,7 @@ actions:
 - name: action_redelegation
   definition:
     kind: synchronous
-    handler: http://localhost:3000/redelegation
+    handler: "{{ACTION_BASE_URL}}/redelegation"
     output_type: ActionRedelegationResponse
     arguments:
     - name: address
@@ -118,7 +118,7 @@ actions:
 - name: action_unbonding_delegation
   definition:
     kind: synchronous
-    handler: http://localhost:3000/unbonding_delegation
+    handler: "{{ACTION_BASE_URL}}/unbonding_delegation"
     output_type: ActionUnbondingDelegationResponse
     arguments:
     - name: address
@@ -141,7 +141,7 @@ actions:
 - name: action_unbonding_delegation_total
   definition:
     kind: synchronous
-    handler: http://localhost:3000/unbonding_delegation_total
+    handler: "{{ACTION_BASE_URL}}/unbonding_delegation_total"
     output_type: ActionBalance
     arguments:
     - name: address
@@ -159,7 +159,7 @@ actions:
 - name: action_validator_commission_amount
   definition:
     kind: synchronous
-    handler: http://localhost:3000/validator_commission_amount
+    handler: "{{ACTION_BASE_URL}}/validator_commission_amount"
     output_type: "[ActionValidatorCommissionAmount]"
     arguments:
     - name: address
@@ -174,7 +174,7 @@ actions:
 - name: action_validator_delegations
   definition:
     kind: synchronous
-    handler: http://localhost:3000/validator_delegations
+    handler: "{{ACTION_BASE_URL}}/validator_delegations"
     output_type: ActionDelegationResponse
     arguments:
     - name: address
@@ -195,7 +195,7 @@ actions:
 - name: action_validator_redelegations_from
   definition:
     kind: synchronous
-    handler: http://localhost:3000/validator_redelegations_from
+    handler: "{{ACTION_BASE_URL}}/validator_redelegations_from"
     output_type: ActionRedelegationResponse
     arguments:
     - name: address
@@ -218,7 +218,7 @@ actions:
 - name: action_validator_unbonding_delegations
   definition:
     kind: synchronous
-    handler: http://localhost:3000/validator_unbonding_delegations
+    handler: "{{ACTION_BASE_URL}}/validator_unbonding_delegations"
     output_type: ActionUnbondingDelegationResponse
     arguments:
     - name: address