Clarify the M1 shell instructions
The instructions seemed to encourage the misconception that `arch -x86_64 zsh` somehow modifies the default architecture for `zsh`, an operation which would need to be "reverted".
In fact, `arch -x86_64 …` merely spawns a new process under the selected architecture.
diff --git a/README.md b/README.md
index b60a8c2..8f6caec 100644
--- a/README.md
+++ b/README.md
@@ -919,13 +919,13 @@
$ nvm install v12.20.1
# Now uninstall the version we want to replace:
$ nvm uninstall v14.15.4
-# Set the architecture for our shell to 64-bit X86:
+# Launch a new zsh process under the 64-bit X86 architecture:
$ arch -x86_64 zsh
# Install node using nvm. This should download the precompiled x64 binary:
$ nvm install v14.15.4
# Now check that the architecture is correct:
$ node -p process.arch
x64
-# It is now safe to revert zsh back to the native architecture:
-$ arch -arm64 zsh
+# It is now safe to return to the arm64 zsh process:
+$ exit
```
