chore: fix release previous tag auto-selection (#607)

GitHub's (un-documented) algorithm for automatically selecting the
previous release tag when generating release notes appears to be
hindered by the presence of our nested go module tags. So we explicitly
select the previous non-pre, non-draft release as the previous tag.

Author: RomainMuller

.github/workflows/release.yml

@@ -63,8 +63,25 @@ jobs:
       # If the release does not yet exist, create a draft release targeting this commit.
       - name: Create draft release
         if: github.event_name == 'push' && steps.version.outputs.exists == 'false'
+        # We explicitly set the notes start tag because GitHub otherwise does not make the right
+        # decision (it is very sensitive to non-version tags being present in the repository, and
+        # the Go nexted modules tags hinder it). We pick the latest non-prerelease tag as the start
+        # tag, always.
         run: |-
-          gh release create '${{ steps.version.outputs.tag }}' --draft --generate-notes --target='${{ github.sha }}' --title='${{ steps.version.outputs.tag }}' ${{ contains(steps.version.outputs.tag, '-') && '--prerelease' || '' }}
+          lastTag=$(gh release list                                                                 \
+            --exclude-drafts                                                                        \
+            --exclude-pre-releases                                                                  \
+            --limit=1                                                                               \
+            --json=tagName                                                                          \
+            --template="{{ (index . 0).tagName }}"                                                  \
+          )
+          gh release create '${{ steps.version.outputs.tag }}'                                      \
+            --draft                                                                                 \
+            --generate-notes                                                                        \
+            --target='${{ github.sha }}'                                                            \
+            --title='${{ steps.version.outputs.tag }}'                                              \
+            --notes-start-tag="${lastTag}"                                                          \
+            ${{ contains(steps.version.outputs.tag, '-') && '--prerelease' || '' }}
         env:
           GH_TOKEN: ${{ github.token }}