docs: update README.md links (#169)

README.md

@@ -66,7 +66,7 @@ npm install @govtechsg/document-store-ethers-v5
 
 ### Document Store
 
-For a complete list of functions, refer to [IDocumentStoreBatchable.sol](src/interfaces/IDocumentStoreBatchable.sol).
+For a complete list of functions, refer to [IDocumentStoreBatchable.sol](https://github.com/Open-Attestation/document-store/blob/master/src/interfaces/IDocumentStoreBatchable.sol).
 
 #### Issuing a document:
 
@@ -137,7 +137,7 @@ await tx.wait();
 
 ### Transferable Document Store
 
-For a complete list of functions, refer to [ITransferableDocumentStore.sol](src/interfaces/ITransferableDocumentStore.sol).
+For a complete list of functions, refer to [ITransferableDocumentStore.sol](https://github.com/Open-Attestation/document-store/blob/master/src/interfaces/ITransferableDocumentStore.sol).
 
 #### Issuing a transferable document:
 
@@ -253,13 +253,13 @@ Most EVM-based blockchains should support the document store contracts. For the
 - Optimism
 
 > [!NOTE]
-> For a list of pre-configured network names for passing to `--network` during deployment, refer to the [foundry.toml](foundry.toml#L28) file.
+> For a list of pre-configured network names for passing to `--network` during deployment, refer to the [foundry.toml](https://github.com/Open-Attestation/document-store/blob/master/foundry.toml#L28) file.
 
 If you wish to deploy to a network not configured yet, you can add it to the `foundry.toml` file and pass the name of the network you've added to `--network` during deployment.
 
 ## Configuration
 
-Create a `.env` file based on [`.env.example`](.env.sample) and provide the information in it.
+Create a `.env` file based on [`.env.example`](https://github.com/Open-Attestation/document-store/blob/master/.env.sample) and provide the information in it.
 
 The `DEPLOYER_ADDRESS` is required to be the address of the deployer during deployment. The Etherscan API keys are only required if you plan to verify the contracts on their respective chains.