Revert "weston-ini-conf: Add agl-shell-grpc-server"

Revert "weston-ini-conf: Add agl-shell-grpc-server"

This reverts commit 2f40613cbf42fd378feea57ccefbb3215ecc1355.

Reason for revert: This breaks the runtime with:
Jan 25 04:07:51 qemuarm agl-compositor[456]: malformed section header: [shell-client-ext]\ncommand=/usr/lib/agl-compositor/agl-shell-grpc-server\n
Jan 25 04:07:51 qemuarm agl-compositor[456]: [04:07:51.432] fatal: error opening or reading config file '/etc/xdg/weston/weston.ini'.

Change-Id: I09f74614a9d7ec55550d46224ec1c1b96528eb0b
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/28354
Tested-by: Jenkins Job builder account
ci-image-build: Jenkins Job builder account
ci-image-boot-test: Jenkins Job builder account
Reviewed-by: Marius Vlad <marius.vlad@collabora.com>
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>