Mac docs update (#847)

Author: levkk

pgml-dashboard/content/docs/guides/setup/v2/installation.md

@@ -93,39 +93,24 @@ version accordingly if yours is different. Other flavors of Linux should work, b
 
 5. Install [pgrx](https://github.com/tcdi/pgrx) and build the extension (this will take a few minutes):
 
-    <strong>With Python Support:</strong>
+    <strong>With Python:</strong>
 
     ```
     export POSTGRES_VERSION=15
     cargo install cargo-pgrx --version "0.9.8" --locked && \
-    cargo pgrx init --pg${POSTGRES_VERSION} /usr/bin/pg_config && \
-    cargo pgrx package
+    cargo pgrx install --pg-config /usr/bin/pg_config
     ```
 
-    <strong>Without Python Support:</strong>
+    <strong>Without Python:</strong>
     ```
     export POSTGRES_VERSION=15
     cp docker/Cargo.toml.no-python Cargo.toml && \
     cargo install cargo-pgrx --version "0.9.8" --locked && \
-    cargo pgrx init --pg${POSTGRES_VERSION} /usr/bin/pg_config && \
-    cargo pgrx package
-    ```
-
-6. Copy the extension binaries into Postgres system folders:
-    ```
-    export POSTGRES_VERSION=15
-    # Copy the extension .so
-    sudo cp target/release/pgml-pg${POSTGRES_VERSION}/usr/lib/postgresql/${POSTGRES_VERSION}/lib/* \
-    /usr/lib/postgresql/${POSTGRES_VERSION}/lib
-    # Copy the control & SQL files
-    sudo cp target/release/pgml-pg${POSTGRES_VERSION}/usr/share/postgresql/${POSTGRES_VERSION}/extension/* \
-    /usr/share/postgresql/${POSTGRES_VERSION}/extension
+    cargo pgrx install --pg-config /usr/bin/pg_config
     ```
 
 === "From Source (Mac)"
 
-<i>N.B:</i> Apple M1s have an issue with `openmp` which XGBoost and LightGBM depend on; some additional steps are required. See this [issue](https://github.com/postgresml/postgresml/issues/364) for more details.
-
 1. Install the latest Rust compiler from [rust-lang.org](https://www.rust-lang.org/learn/get-started).
 
 2. Clone our git repository:
@@ -138,14 +123,13 @@ version accordingly if yours is different. Other flavors of Linux should work, b
 
 3. Install PostgreSQL and other dependencies:
     ```
-    brew install llvm postgresql cmake openssl pkg-config
+    brew install llvm postgresql@15 cmake openssl pkg-config openblas libomp
     ```
 
 4. Install [pgrx](https://github.com/tcdi/pgrx) and build the extension (this will take a few minutes):
     ```
     cargo install cargo-pgrx && \
-    cargo pgrx init --pg15 /usr/bin/pg_config && \
-    cargo pgrx install
+    cargo pgrx install --pg-config /opt/homebrew/opt/postgresql@15/bin/pg_config
     ```
 
 ===
@@ -160,12 +144,24 @@ PostgresML needs to be preloaded at server startup, so you need to add it into `
 shared_preload_libraries = 'pgml,pg_stat_statements'
 ```
 
+On Ubuntu, this can be configured by changing `/etc/postgresql/15/main/postgresql.conf`. On Mac, the config file is located in `/opt/homebrew/var/postgresql@15/postgresql.conf`.
+
 This setting change requires PostgreSQL to be restarted:
 
+=== "Ubuntu"
+
 ```bash
 sudo service postgresql restart
 ```
 
+=== "Mac"
+
+```bash
+brew services restart postgresql@15
+```
+
+===
+
 #### Install into database
 
 !!! note