Make disposable-email list reference-able from Earthly builds

[idelvall]

Having this Earthfile (see https://github.com/earthly/earthly) in your folder would help all Earthly users referencing this list in their build scripts (benefiting from the Earthly build cache).

This is how a referencing Earthfile would look like:

VERSION 0.7
FROM alpine:3.18.4

get-disposable-emails:
  COPY github.com/MISP/misp-warninglists/lists/disposable-email+export/list.json ./
  RUN cat list.json | head -n 10

And an example of its execution:

$ earthly +get-disposable-emails
 Init 🚀
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           buildkitd | Found buildkit daemon as docker container (earthly-buildkitd)

Streaming logs to https://cloud.earthly.dev/builds/a9cb7865-d4dd-4123-9715-9c8886e79480

 Build 🔧
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       alpine:3.18.4 | --> Load metadata alpine:3.18.4 linux/amd64
g/e/m/l/disposable-email+base | --> FROM alpine:3.18.4
g/e/m/l/disposable-email+base | [----------] 100% FROM alpine:3.18.4
g/e/m/l/disposable-email+export | *cached* --> COPY list.json ./
+get-disposable-emails | *cached* --> COPY github.com/earthly/misp-warninglists/lists/disposable-email+export/list.json ./
+get-disposable-emails | --> RUN cat list.json | head -n 10
+get-disposable-emails | {
+get-disposable-emails |   "description": "List of disposable email domains",
+get-disposable-emails |   "list": [
+get-disposable-emails |     "0-mail.com",
+get-disposable-emails |     "027168.com",
+get-disposable-emails |     "0815.ru",
+get-disposable-emails |     "0815.ry",
+get-disposable-emails |     "0815.su",
+get-disposable-emails |     "0845.ru",
+get-disposable-emails |     "0box.eu",
              output | --> exporting outputs

 Push Summary ⏫ (disabled)
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To enable pushing use earthly --push

 Local Output Summary 🎁
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========================== 🌍 Earthly Build  ✅ SUCCESS ==========================

View logs at https://cloud.earthly.dev/builds/a9cb7865-d4dd-4123-9715-9c8886e79480

[adulau]

Thank you for the pull request. I'm not entirely sure about the advantage of having a kind-of Makefile in a specific directory for a single list of MISP warning lists.

If there's a specific need for deployment scripts, I would suggest placing an Earth file at the top of the project directory. The directory structure for warning lists expects a single JSON file in the specification.

[idelvall]

Hi Alexandre, the goal is to make our builds explicit about which are the sources of truth involved in it, and the same time get your updates in a timely and performant way. I focused on the solving our immediate needs in the less intrusive way, that is why I placed the Earthfile there, but placing at the top level have more sense now that you mentioned it.
Let me work on that

[adulau]

Thank you for the updates and contribution.

[idelvall]

Thanks to you for maintaining these lists. They are useful!