Publish tagged images of loki-canary-boringcrypto (#10386)

**What this PR does / why we need it**:
Examining the images contained in the loki-canary repo (
https://hub.docker.com/repository/docker/grafana/loki-canary/tags?page=1&ordering=last_updated
) compared to the loki-canary-boringcrypto repo (
https://hub.docker.com/repository/docker/grafana/loki-canary-boringcrypto/tags?page=1&ordering=last_updated
), it appears that the explicitly tagged images (such as 'main') are not
being sent to the boringcrypto repo.

This PR is to adjust that behavior so that both repos receive the same
number of builds (one will be boringcrypto enabled, the other will not
be)

**Which issue(s) this PR fixes**:
Fixes #<issue number>

**Special notes for your reviewer**:

**Checklist**
- [ ] Reviewed the
[`CONTRIBUTING.md`](https://github.com/grafana/loki/blob/main/CONTRIBUTING.md)
guide (**required**)
- [ ] Documentation added
- [ ] Tests updated
- [ ] `CHANGELOG.md` updated
- [ ] If the change is worth mentioning in the release notes, add
`add-to-release-notes` label
- [ ] Changes that require user attention or interaction to upgrade are
documented in `docs/sources/setup/upgrade/_index.md`
- [ ] For Helm chart changes bump the Helm chart version in
`production/helm/loki/Chart.yaml` and update
`production/helm/loki/CHANGELOG.md` and
`production/helm/loki/README.md`. [Example
PR](d10549e3ec)

.drone/drone.jsonnet

@@ -695,7 +695,7 @@ local manifest_ecr(apps, archs) = pipeline('manifest-ecr') {
   fluentd(),
   logstash(),
   querytee(),
-  manifest(['promtail', 'loki', 'loki-canary', 'fluent-bit']) {
+  manifest(['promtail', 'loki', 'loki-canary', 'fluent-bit', 'loki-canary-boringcrypto']) {
     trigger+: onTagOrMain,
   },
   manifest_operator('loki-operator') {

.drone/drone.yml

@@ -1427,6 +1427,19 @@ steps:
     target: fluent-bit
     username:
       from_secret: docker_username
+- depends_on:
+  - clone
+  - manifest-fluent-bit
+  image: plugins/manifest:1.4.0
+  name: manifest-loki-canary-boringcrypto
+  settings:
+    ignore_missing: false
+    password:
+      from_secret: docker_password
+    spec: .drone/docker-manifest.tmpl
+    target: loki-canary-boringcrypto
+    username:
+      from_secret: docker_username
 trigger:
   event:
   - push
@@ -2003,6 +2016,6 @@ kind: secret
 name: gpg_private_key
 ---
 kind: signature
-hmac: fb384b17b46ac77869765efc735c4d389ba33e37d5c584ec93da7b4c6b0387da
+hmac: d53b81539e55f3be9f946e7270740c8f6c264ffb4030d7040b2fcb136927606c
 
 ...