Update dockerfile deps (#29808)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| alpine | final | minor | `3.18` -> `3.19` |
| python | final | minor | `3.11-slim` -> `3.12-slim` |

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examples/demo/client/Dockerfile

@@ -5,6 +5,6 @@ WORKDIR /app/
 COPY . .
 RUN go env -w GOPROXY=direct
 RUN CGO_ENABLED=0 go build -o main main.go
-FROM alpine:3.18
+FROM alpine:3.19
 COPY --from=build /app/main  /app/main
 CMD ["/app/main"]

examples/demo/server/Dockerfile

@@ -5,6 +5,6 @@ WORKDIR /app/
 COPY . .
 RUN go env -w GOPROXY=direct
 RUN CGO_ENABLED=0 go build -o main main.go
-FROM alpine:3.18
+FROM alpine:3.19
 COPY --from=build /app/main  /app/main
 CMD ["/app/main"]

receiver/snmpreceiver/testdata/integration/docker/snmp_agent.Dockerfile

@@ -1,5 +1,5 @@
 # https://github.com/maxgio92/docker-snmpsim
-FROM python:3.11-slim
+FROM python:3.12-slim
 
 RUN pip install snmpsim