add curl to images (#140)

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Closes: #XXX

## What is the purpose of the change

> Add a description of the overall background and high level changes
that this PR introduces

*(E.g.: This pull request improves documentation of area A by adding
....)*

## Testing and Verifying

*(Please pick one of the following options)*

This change is a trivial rework / code cleanup without any test
coverage.

*(or)*

This change is already covered by existing tests, such as *(please
describe tests)*.

*(or)*

This change added tests and can be verified as follows:

*(example:)*
  - *Added unit test that validates ...*
  - *Added integration tests for end-to-end deployment with ...*
  - *Extended integration test for ...*
  - *Manually verified the change by ...*

## Documentation and Release Note

- [ ] Does this pull request introduce a new feature or user-facing
behavior changes?


Where is the change documented?
  - [ ] Specification (`x/{module}/README.md`)
- [ ] Allora documentation site `docs.allora.network` source code at:
`https://github.com/allora-network/docs`
  - [ ] Code comments?
  - [ ] N/A

docker/Dockerfile_head

@@ -21,7 +21,8 @@ RUN apt update && \
     apt -y dist-upgrade && \
     apt install -y --no-install-recommends \
       tzdata \
-      ca-certificates && \
+      ca-certificates \
+      curl && \
     echo "deb http://deb.debian.org/debian testing main" >> /etc/apt/sources.list && \
     apt update && \
     apt install -y --no-install-recommends -t testing \

docker/Dockerfile_worker

@@ -23,7 +23,8 @@ RUN apt update && \
       tzdata \
       ca-certificates \
       libssl-dev \
-      gh && \
+      gh \
+      curl && \
     echo "deb http://deb.debian.org/debian testing main" >> /etc/apt/sources.list && \
     apt update && \
     apt install -y --no-install-recommends -t testing \

docker/Dockerfile_worker_py3.9

@@ -23,7 +23,8 @@ RUN apt update && \
       tzdata \
       ca-certificates \
       libssl-dev \
-      gh && \
+      gh \
+      curl && \
     echo "deb http://deb.debian.org/debian testing main" >> /etc/apt/sources.list && \
     apt update && \
     apt install -y --no-install-recommends -t testing \