entproto: implement list service method (ent#162)

* entproto: generate list method for service annotations

For #2107

* protoc-gen-entgrpc: generate list method handler code

For #2107

* entproto: re-generate schema

For #2107

* entproto: implement list method unit test

For #2107

* entproto: appease the linter

For #2107

* entproto: fix typo in service.go

For #2107

* protoc-gen-entgrpc: add base64 encoding to page token

For #2107

* entproto: re-generate schema

For #2107

* entproto: increase MaxPageSize

For #2107

* entproto: change page token to string

For #2107

* entproto: revert infra change

For #2107

* protoc-gen-entgrpc: simplify page token wrapping

For #2107

* entproto: re-generate schema

For #2107

* entproto: simplify list method test

For #2107

* protoc-gen-entgrpc: throw template error for unsupported id types

* protoc-gen-entgrpc: adjust formatting in method_list.tmpl

Co-authored-by: Ariel Mashraki <7413593+a8m@users.noreply.github.com>

* entproto: adjust formatting in service.go

Co-authored-by: Ariel Mashraki <7413593+a8m@users.noreply.github.com>

* entproto: go fmt service.go

* entproto: re-generate schema

* entproto: throw error in list method proto generation for unsupported id

* protoc-gen-entgrpc: remove throwError

* entproto: re-generate schema

Co-authored-by: Ariel Mashraki <7413593+a8m@users.noreply.github.com>

all: enable dependabot (ent#117)

Main repo already uses it, why should'nt this one? ent has had two releases already.