update checkout to v6

Author: scarlehoff

.github/actions/install_conda_pip/action.yml

@@ -17,7 +17,7 @@ name: Install nnpdf using pip under a conda environment
 #
 # Remember that these actions are only available after checking out the repository,
 # which should always be the first step!
-# - uses: actions/checkout@v4
+# - uses: actions/checkout@v6
 
 inputs:
   python-version:

.github/actions/prepare_environment/action.yml

@@ -13,7 +13,7 @@ name: Prepare a conda environment for NNPDF installation
 #
 # Remember that these actions are only available after checking out the repository,
 # which should always be the first step!
-# - uses: actions/checkout@v4
+# - uses: actions/checkout@v6
 #
 # This action also removes part of the cache of the runner to avoid using too much storage
 # (see at the bottom)

.github/workflows/all_tests_nnpdf.yml

@@ -28,7 +28,7 @@ jobs:
       fail-fast: false # continue even if some jobs failed
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/install_conda_pip
         with:
           python-version: ${{ matrix.python-version }}
@@ -48,10 +48,8 @@ jobs:
   regression_tests:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/install_conda_pip
-        with:
-          nnpdf-extras: "[qed,tests]"
       - name: Run regression tests
         shell: bash -l {0}
         run: |
@@ -70,7 +68,7 @@ jobs:
       fail-fast: false
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with: # conda requires fetching the history of the repo to prepare the package name
           fetch-tags: true
           fetch-depth: 0
@@ -95,7 +93,7 @@ jobs:
     env:
       KERAS_BACKEND: torch
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - uses: actions/setup-python@v5
       with:
         python-version: "3.13"
@@ -127,7 +125,7 @@ jobs:
     env:
       KERAS_BACKEND: jax
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - uses: actions/setup-python@v5
       with:
         python-version: "3.13"
@@ -148,7 +146,7 @@ jobs:
     needs: [run_package_tests, regression_tests]
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - uses: ./.github/actions/install_conda_pip
       with:
         nnpdf-extras: ""

.github/workflows/check_newcd.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-tags: true
           fetch-depth: 0

.github/workflows/fitbot.yml

@@ -22,7 +22,7 @@ jobs:
     if: contains(github.event.pull_request.labels.*.name, 'run-fit-bot')
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
       with:
         fetch-tags: true
         fetch-depth: 0

.github/workflows/redo_regressions.yml

@@ -1,6 +1,8 @@
 name: Redo regressions
 
-# start job only for PRs when a label is added.
+# Last update: 17/03/2026
+
+# start job only for PRs when a label is added
 on:
   pull_request:
     types: [labeled]
@@ -18,7 +20,7 @@ jobs:
       NETRC_FILE: ${{ secrets.NETRC_FILE }}
       NNPDF_SSH_KEY: ${{ secrets.NNPDF_SSH_KEY }}
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0
         ref: ${{ github.event.pull_request.head.ref }}

.github/workflows/regenerate_data.yml

@@ -10,7 +10,7 @@ jobs:
     if: contains(github.event.pull_request.labels.*.name, 'regenerate-data')
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0
           ref: ${{ github.event.pull_request.head.ref }}

.github/workflows/upload_docs.yml

@@ -10,7 +10,7 @@ jobs:
   deploy_docs:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/install_conda_pip
         with:
           nnpdf-extras: "[qed,docs]"