[ENH] add caching action for elephant-data #1

	name: Create caches for elephant_data

	on:
	workflow_dispatch: # Workflow can be triggered manually via GH actions webinterface
	push: # When something is pushed into master this checks if caches need to re-created
	branches:
	- master
	schedule:
	- cron: "0 12 * * *" # Daily at noon UTC

	pull_request:
	branches:
	- master
	types:
	- opened
	- reopened
	- synchronize

	jobs:
	create-data-cache-if-missing:
	name: Caching data env
	runs-on: "macos-latest"
	steps:

	- name: Get current hash (SHA) of the elephant_data repo
	id: elephant-data
	run: \|
	echo "dataset_hash=$(git ls-remote https://gin.g-node.org/NeuralEnsemble/elephant-data.git HEAD \| cut -f1)" >> $GITHUB_OUTPUT

	- uses: actions/cache@v3
	# Loading cache of elephant-data
	id: cache-datasets
	with:
	path: ~/elephant-data
	key: ${{ runner.os }}-datasets-${{ steps.elephant-data.outputs.dataset_hash }}

	- name: Cache found?
	run: echo "Cache-hit == ${{steps.cache-datasets.outputs.cache-hit == 'true'}}"

	- name: Installing gin
	if: steps.cache-datasets.outputs.cache-hit != 'true'
	run: \|
	git config --global user.email "elephant_ci@fake_mail.com"
	git config --global user.name "elephant CI"
	git config --global filter.annex.process "git-annex filter-process" # recommended for efficiency

	brew tap g-node/pkg
	brew install g-node/pkg/gin-cli

	- name: Download dataset
	if: steps.cache-datasets.outputs.cache-hit != 'true'
	# Download repository and also fetch data
	run: \|
	gin --version

	- name: Show size of the cache to assert data is downloaded
	run: \|
	cd ~
	pwd
	du -hs elephant-data
	cd elephant-data
	pwd

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