chore(ci): small notes for the build steps (#54073)

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### What?

Leaving a small note to the build steps to avoid regressions like
#54017 later.


Closes WEB-1386

---------

Co-authored-by: Steven <steven@ceriously.com>

.github/workflows/build_and_deploy.yml

@@ -145,6 +145,13 @@ jobs:
               - 'metal'
 
             target: 'x86_64-unknown-linux-gnu'
+            # [NOTE] If you want to update / modify build steps, check these things:
+            # - We use docker images to pin the glibc version to link against,
+            #   even if host target is identical to the container image (i.e host: x64-linux, image: x64-linux)
+            # - After build `objdump -T` prints out the glibc version next-swc is linked against,
+            #   to ensure it did not change unexpectedly if docker image, or other dependency changed
+            # - zig linker with portable glibc is avoided as it has known issues with static tls + node.js + multi threaded
+            #   environment.
             docker: ghcr.io/napi-rs/napi-rs/nodejs-rust:stable-2022-10-24-x64
             build: >-
               set -e &&