.dockerignore: exclude devtools/config and e2e directories
.dockerignore: exclude devtools/config and e2e directories

Change-Id: I6e3d1df9ec55e3bd3ec3b1f3383c9a218dc8b868
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/292692
Reviewed-by: Julie Qiu <8d32267b6b4884cf35adeaccde2b6857ae11aace@golang.org>
Trust: Jamal Carvalho <e0195770807aa8c82b0b128d9c0423b5ad035172@golang.org>

golang/pkgsite,golang/pkgsite,golang/pkgsite,golang/pkgsite