Replacing docker images is broken if using helm-like syntax

[aboukhal]

How are you running Renovate?

Self-hosted Renovate CLI

Which platform you running Renovate on?

Other (please specify)

Which version of Renovate are you using?

44.40.0

Please tell us more about your question or problem

I have observed that renovate will not honor dependency replacements when trying to replace docker images that are not defined in a single string but rather split up into several fields.

This is the rule we've come up with:

        {
            "description": "Ersetze ose-cli durch ose-cli-rhel9",
            "matchDatasources": [
                "docker"
            ],
            "matchPackageNames": [
                "registry.redhat.io/openshift4/ose-cli"
            ],
            "replacementName": "registry.redhat.io/openshift4/ose-cli-rhel9",
            "replacementVersion": "v4.18.0"
        }

This works perfectly file for example 1 and produces the correct pull request.

# Example 1 (values.yaml)
test:
  image: registry.redhat.io/openshift4/ose-cli:v4.15@sha256:444ad86f37930b0238c67d254c5902825249b6c67903b7d5725a05a05173e0f7

On example 2, however, renovate just prints out an unclear message.

# Example 2 (values.yaml)
test:
  image:
    registry: registry.redhat.io
    repository: openshift4/ose-cli
    tag: v4.15@sha256:444ad86f37930b0238c67d254c5902825249b6c67903b7d5725a05a05173e0f7
    pullPolicy: IfNotPresent

Here's the message:

DEBUG: manager.getUpdatedPackageFiles() reuseExistingBranch=false (repository=internal/test-renovatedev, branch=renovate/registry.redhat.io-openshift4-ose-cli-replacement)
 INFO: Cannot find replaceString in current file content. Was it already updated? (repository=internal/test-renovatedev, packageFile=values.yaml, branch=renovate/registry.redhat.io-openshift4-ose-cli-replacement)
       "depName": "registry.redhat.io/openshift4/ose-cli",
       "existingContent": "test:\n  image:\n    registry: registry.redhat.io\n    repository: openshift4/ose-cli\n    tag: v4.15\n    pullPolicy: IfNotPresent\n",
       "replaceString": "v4.15"

I'm not sure what I'm missing to enable replacements in helm charts as well.

Logs (if relevant)

Logs

Replace this text with your logs, between the starting and ending triple backticks