_content/blog: fix list item formatting in rebuild.md

It was meant to be one bullet point, not two.

Change-Id: I113f1cef44319f95aff110c6f3ef1d1dad9a69b2
Reviewed-on: https://go-review.googlesource.com/c/website/+/524396
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Russ Cox <rsc@golang.org>

_content/blog/rebuild.md

@@ -77,7 +77,7 @@ Common relevant inputs to a build include:
   - the specific versions of dependencies that will be included in the build;
   - the operating system running the build, which may affect path names in the resulting binaries;
   - the architecture of the CPU on the build system,
-  - which may affect which optimizations the compiler uses or the layout of certain data structures;
+    which may affect which optimizations the compiler uses or the layout of certain data structures;
   - the compiler version being used, as well as compiler options passed to it, which affect how the code is compiled;
   - the name of the directory containing the source code, which may appear in debug information;
   - the user name, group name, uid, and gid of the account running the build, which may appear in file metadata in an archive;