docs: fix apt command in gc.md and add cmake note to build guide

Signed-off-by: Ankit Ram <ankiittt15@gmail.com>

Author: Ankitdotraider

docs/contribute/source/build_from_src.md

@@ -108,6 +108,8 @@ Developers can follow the steps to build WasmEdge with plug-ins from source.
 - [WasmEdge-StableDiffusion](plugin/wasmedge_stablediffusion.md)
 - [WasmEdge-zlib](plugin/wasmedge_zlib.md)
 
+> Note: Each plug-in guide above includes the corresponding `-DWASMEDGE_PLUGIN_*` CMake option.
+
 ## Run Tests
 
 The tests are only available when the build option `WASMEDGE_BUILD_TESTS` is set to `ON`.

docs/start/wasmedge/extensions/gc.md

@@ -20,7 +20,8 @@ This is enabled by default in WasmEdge since `0.16.0`. For WasmEdge `0.14.x`–`
 Install WABT on Linux:
 
 ```bash
-apt install wabt
+sudo apt update
+sudo apt install -y wabt
 ```
 
 Or on macOS: