[components] Don't use bare package URLs.

- Just remove the build flag, all usages of sessionmgr,
dev_session_shell, and suggestion_engine are in fuchsia pkg URL format
already

CF-335 #done
CF-311 #done

TESTED: CQ
Change-Id: Ie144d54fd73e5d1f2aa83b6cb9e071180754e1f0
diff --git a/bin/sessionmgr/BUILD.gn b/bin/sessionmgr/BUILD.gn
index 335c73d..f49eb6e 100644
--- a/bin/sessionmgr/BUILD.gn
+++ b/bin/sessionmgr/BUILD.gn
@@ -5,8 +5,6 @@
 import("//peridot/build/executable_package.gni")
 
 executable_package("sessionmgr") {
-  deprecated_bare_package_url = "//build"
-
   meta = [
     {
       path = "meta/sessionmgr.cmx"
@@ -94,8 +92,6 @@
 }
 
 executable_package("dev_session_shell") {
-  deprecated_bare_package_url = "//build"
-
   meta = [
     {
       path = "meta/dev_session_shell.cmx"
diff --git a/bin/suggestion_engine/BUILD.gn b/bin/suggestion_engine/BUILD.gn
index c031a18..bbf2ae8 100644
--- a/bin/suggestion_engine/BUILD.gn
+++ b/bin/suggestion_engine/BUILD.gn
@@ -6,8 +6,6 @@
 import("//peridot/build/tests_package.gni")
 
 executable_package("suggestion_engine") {
-  deprecated_bare_package_url = "//build"
-
   meta = [
     {
       path = "meta/suggestion_engine.cmx"