ci: Only download required repositories

This should speed up CI a bit.

.github/project.yml

@@ -30,3 +30,7 @@ repository.apache-mynewt-core:
     vers: 0.0.0
     user: apache
     repo: mynewt-core
+
+project.repositories.ignored:
+       - stm-*
+       - atmel-samd21xx

.github/project_newt_test_all.yml

@@ -0,0 +1,39 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+project.name: "my_project"
+
+project.repositories:
+    - apache-mynewt-core
+
+# Use github's distribution mechanism for core ASF libraries.
+# This provides mirroring automatically for us.
+#
+repository.apache-mynewt-core:
+    type: github
+    vers: 0.0.0
+    user: apache
+    repo: mynewt-core
+
+project.repositories.allowed:
+       - apache-mynewt-core
+       - apache-mynewt-nimble
+       - apache-mynewt-mcumgr
+       - mcuboot
+       - mbedtls

.github/workflows/newt_test_all.yml

@@ -49,7 +49,7 @@ jobs:
         shell: bash
         run: |
              newt new build
-             cp -f .github/project.yml build/project.yml
+             cp -f .github/project_newt_test_all.yml build/project.yml
              cd build
              newt upgrade --shallow=1
              rm -rf repos/apache-mynewt-nimble