Update sui-install.mdx to add libpq to dependency (MystenLabs#15878)

title

## Description 

title

## Test Plan 

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![Screenshot 2024-01-23 at 4 03
53 PM](https://github.com/MystenLabs/sui/assets/106119108/ab14418c-b9ec-4a0d-9a3f-135588abe7c4)



---
If your changes are not user-facing and do not break anything, you can
skip the following section. Otherwise, please briefly describe what has
changed under the Release Notes section.

### Type of Change (Check all that apply)

- [ ] protocol change
- [ ] user-visible impact
- [ ] breaking change for a client SDKs
- [ ] breaking change for FNs (FN binary must upgrade)
- [ ] breaking change for validators or node operators (must upgrade
binaries)
- [ ] breaking change for on-chain data layout
- [ ] necessitate either a data wipe or data migration

### Release notes

docs/content/guides/developer/getting-started/sui-install.mdx

@@ -223,6 +223,7 @@ The prerequisites needed for the macOS operating system include:
 - Homebrew
 - cURL
 - CMake
+- libpq
 - Git CLI
 
 macOS includes a version of cURL you can use to install Homebrew. Use Homebrew to install other tools, including a newer version of cURL.
@@ -268,6 +269,12 @@ brew install cmake
 
 To customize the installation, see [Installing CMake](https://cmake.org/install/) on the CMake website.
 
+#### libpq {#libpq-1}
+Use the following command to install libpq:
+```bash
+brew install libpq
+```
+
 #### Git CLI {#git-cli-1}
 
 Use the following command to install Git: