release: generate CHANGELOG from git history

[sauterp]

Running this in the CSI repo you'd see something like this:

❯ make prepare-release
Error: NEW_VERSION is not set. Usage: make prepare-release NEW_VERSION=vX.Y.Z
make: *** [/home/sauterp/src/github.com/exoscale/exoscale-csi-driver/go.mk/release.mk:85: prepare-release] Error 1

❯ make prepare-release NEW_VERSION=v0.29.7
[philippsauter/sc-101978/csi-automate-manifest-release 97f6adf] Prepare release
 1 file changed, 62 deletions(-)
 delete mode 100644 CHANGELOG.md
make[1]: Entering directory '/home/sauterp/src/github.com/exoscale/exoscale-csi-driver'
./go.mk/scripts/generate-release-notes-for-tag.sh v0.29.7 >> CHANGELOG.md
./go.mk/scripts/generate-release-notes-for-tag.sh v0.29.6 >> CHANGELOG.md
./go.mk/scripts/generate-release-notes-for-tag.sh v0.29.5 >> CHANGELOG.md
./go.mk/scripts/generate-release-notes-for-tag.sh v0.29.4 >> CHANGELOG.md
./go.mk/scripts/generate-release-notes-for-tag.sh v0.29.3 >> CHANGELOG.md
./go.mk/scripts/generate-release-notes-for-tag.sh v0.29.2 >> CHANGELOG.md
./go.mk/scripts/generate-release-notes-for-tag.sh v0.29.1 >> CHANGELOG.md
./go.mk/scripts/generate-release-notes-for-tag.sh v0.29.0 >> CHANGELOG.md
make[1]: Leaving directory '/home/sauterp/src/github.com/exoscale/exoscale-csi-driver'
Deleted tag 'v0.29.7' (was 97f6adf)
[philippsauter/sc-101978/csi-automate-manifest-release f8b613b] Prepare release
 Date: Fri Jul 26 13:52:44 2024 +0200
 1 file changed, 53 insertions(+), 59 deletions(-)

The generated changelog will look like this https://github.com/exoscale/exoscale-csi-driver/blob/9ae7906649094e47311fff899d5499b46a9c1eb5/CHANGELOG.md

[pierre-emmanuelJ]

Thanks awesome!
Ideally would be ignored the commit prepare realease in the changelog, otherwise it's 👍

[sauterp]

Thanks awesome! Ideally would be ignored the commit prepare realease in the changelog, otherwise it's 👍

I thought about this, but concluded it's better to keep the prepare release comment, because in the CSI repo we're going to generate manifests with each prepare release commits, so these commits aren't "meaningless", plus it has been spelled differently in some repos. Unless you object I'd keep them. (it's also simpler)