Update BUILDING.md

Author: anonrig

BUILDING.md

@@ -102,7 +102,7 @@ for it. In other words, Node.js does not support running on End-of-Life (EoL)
 platforms. This is true regardless of entries in the table below.
 
 | Operating System | Architectures    | Versions                          | Support Type | Notes                                |
-| ---------------- | ---------------- | --------------------------------- |--------------| ------------------------------------ |
+| ---------------- | ---------------- | --------------------------------- | ------------ | ------------------------------------ |
 | GNU/Linux        | x64              | kernel >= 4.18[^1], glibc >= 2.28 | Tier 1       | e.g. Ubuntu 20.04, Debian 10, RHEL 8 |
 | GNU/Linux        | x64              | kernel >= 3.10, musl >= 1.1.19    | Experimental | e.g. Alpine 3.8                      |
 | GNU/Linux        | x86              | kernel >= 3.10, glibc >= 2.17     | Experimental | Downgraded as of Node.js 10          |