fix: adjust node requirements (#248)

# Description

Adjust external node requirements

## Linked Issues


zkSync-Community-Hub/zksync-developers#742

## Additional context

content/20.zksync-node/05.quickstart.md

@@ -9,6 +9,17 @@ description:
   - [Docker](https://docs.docker.com/get-docker/)
   - [Docker Compose](https://docs.docker.com/compose/install/)
 
+## System Requirements
+
+The following are minimal requirements to run the node using Docker:
+
+- **CPU:** A relatively modern CPU is recommended.
+- **RAM:** 32 GB
+- **Storage:**
+  - **Testnet Nodes:** 30 GB
+  - **Mainnet Nodes:** 300 GB, with the state growing about 1TB per month.
+- **Network:** 100 Mbps connection (1 Gbps+ recommended)
+
 ## Setup Instructions
 
 1. Clone the ZKsync Era repository and navigate to the ZKsync node guide:
@@ -70,17 +81,6 @@ this period, the API server will not serve any requests.
 - **DB Dump:** For nodes that operate from a DB dump, which allows starting a ZKsync node with a full historical
 transactions history, refer to the documentation on running from DB dumps at [03_running.md](https://github.com/matter-labs/zksync-era/blob/main/docs/guides/external-node/03_running.md).
 
-## System Requirements
-
-The following are minimal requirements:
-
-- **CPU:** A relatively modern CPU is recommended.
-- **RAM:** 32 GB
-- **Storage:**
-  - **Testnet Nodes:** 30 GB
-  - **Mainnet Nodes:** 300 GB, with the state growing about 1TB per month.
-- **Network:** 100 Mbps connection (1 Gbps+ recommended)
-
 ## Advanced Setup
 
 For additional configurations like monitoring, backups, recovery from DB dump or snapshot, and custom PostgreSQL

content/20.zksync-node/30.running-node.md

@@ -10,7 +10,7 @@ This section assumes that you have prepared a configuration file as described on
 This configuration is approximate and should be considered as **minimal** requirements.
 
 - 32-core CPU
-- 64GB RAM
+- 32GB RAM
 - SSD storage (NVME recommended):
   - Sepolia Testnet - 10GB ZKsync node + 50GB PostgreSQL (at the time of writing, will grow over time, so should be
     constantly monitored)