Unpin test and upgrade packages (#14282)

* Unpin package:test and upgrade packages

* Update packages/flutter/test/foundation/stack_trace_test.dart

* Also add packages/flutter_tools/test/data/asset_test/font/.dartignore to ensure that update-packages --force-upgrade does not crash.

examples/flutter_gallery/pubspec.yaml

diff --git a/examples/flutter_gallery/pubspec.yaml b/examples/flutter_gallery/pubspec.yaml
index 6e81425..ca2eb9c 100644
--- a/examples/flutter_gallery/pubspec.yaml
+++ b/examples/flutter_gallery/pubspec.yaml
@@ -41,12 +41,13 @@
   io: 0.3.1 # TRANSITIVE DEPENDENCY
   isolate: 1.1.0 # TRANSITIVE DEPENDENCY
   js: 0.6.1 # TRANSITIVE DEPENDENCY
-  json_rpc_2: 2.0.6 # TRANSITIVE DEPENDENCY
+  json_rpc_2: 2.0.7 # TRANSITIVE DEPENDENCY
   logging: 0.11.3+1 # TRANSITIVE DEPENDENCY
   matcher: 0.12.1+4 # TRANSITIVE DEPENDENCY
   meta: 1.1.1 # TRANSITIVE DEPENDENCY
   mime: 0.9.5 # TRANSITIVE DEPENDENCY
   mockito: 2.2.1 # TRANSITIVE DEPENDENCY
+  multi_server_socket: 1.0.1 # TRANSITIVE DEPENDENCY
   node_preamble: 1.4.0 # TRANSITIVE DEPENDENCY
   package_config: 1.0.3 # TRANSITIVE DEPENDENCY
   package_resolver: 1.0.2 # TRANSITIVE DEPENDENCY
@@ -54,7 +55,7 @@
   plugin: 0.2.0+2 # TRANSITIVE DEPENDENCY
   pool: 1.3.4 # TRANSITIVE DEPENDENCY
   pub_semver: 1.3.2 # TRANSITIVE DEPENDENCY
-  quiver: 0.27.0 # TRANSITIVE DEPENDENCY
+  quiver: 0.28.0 # TRANSITIVE DEPENDENCY
   shelf: 0.7.2 # TRANSITIVE DEPENDENCY
   shelf_packages_handler: 1.0.3 # TRANSITIVE DEPENDENCY
   shelf_static: 0.2.7 # TRANSITIVE DEPENDENCY
@@ -65,7 +66,7 @@
   stack_trace: 1.9.1 # TRANSITIVE DEPENDENCY
   stream_channel: 1.6.3 # TRANSITIVE DEPENDENCY
   term_glyph: 1.0.0 # TRANSITIVE DEPENDENCY
-  test: 0.12.26 # TRANSITIVE DEPENDENCY
+  test: 0.12.30+1 # TRANSITIVE DEPENDENCY
   typed_data: 1.1.4 # TRANSITIVE DEPENDENCY
   utf: 0.9.0+3 # TRANSITIVE DEPENDENCY
   vector_math: 2.0.5 # TRANSITIVE DEPENDENCY