[x/blog] blog: change title of ismmkeynote
[x/blog] blog: change title of ismmkeynote

Changed title to
Getting to Go: The Journey of Go's Garbage Collector

Did not change the URL as suggested by Rob. It seems
too late for such a change.

Change-Id: Iff94f637eb51ce431d486b6eed51b14608979a85
Reviewed-on: https://go-review.googlesource.com/124675
Reviewed-by: Andrew Bonventre <682ad9f487f614f19e8b7cc5d340bdc8e1c1b128@golang.org>
X-Blog-Commit: 1750088804985b8380e85dba8ad4a078a606e695

golang/website,golang/website,golang/website,golang/website,golang/website,golang/website,golang/website