docker-compose.yml: specify AMD64 platform (#166)

Several Docker images used by Segment do not work reliably on Mac M1 laptops,
which use the ARM chipset. Commonly, these are images that were built several
years ago, before M1 laptops were in widespread use, and behave unpredictably
when run on an ARM chipset.

The simplest workaround is to ensure that the Docker environment is always
running on x86. This change should ensure that employees with M1 laptops will be
able to reliably start and run Docker containers on this repository.

docker-compose.yml

@@ -2,17 +2,28 @@ services:
   influxdb:
     image: influxdb:alpine
     ports:
-      - 8086:8086
-
+    - 8086:8086
+
+    # If you are on arm64 and experiencing issues with the tests (hangs,
+    # connection reset) then try the following in order:
+
+    # - stopping and removing all downloaded container images
+    # - ensuring you have the latest Docker Desktop version
+    # - factory reset your Docker Desktop settings
+
+    # If you are still running into issues please post in #help-infra-seg.
+    platform: linux/amd64
   otel-collector:
     image: otel/opentelemetry-collector:0.48.0
     command:
-      - "/otelcol"
-      - "--config=/etc/otel-config.yaml"
+    - "/otelcol"
+    - "--config=/etc/otel-config.yaml"
     ports:
-      - 4317:4317
-      - 4318:4318
-      - 4319:4319
-      - 8888:8888
+    - 4317:4317
+    - 4318:4318
+    - 4319:4319
+    - 8888:8888
     volumes:
-      - "./.otel/config.yaml:/etc/otel-config.yaml"
+    - "./.otel/config.yaml:/etc/otel-config.yaml"
+    # See platform comment above for amd64/arm64 troubleshooting
+    platform: linux/amd64