feat: allow encrypted secrets file syntax for checksum updates

[CharlieDixon]

Adds a helper function to allow the checksum/secrets annotation to be updated in response to changes in both the default secret.yaml file, as well as any files which match the wildcard patterns *secrets.yaml.encrypted or *secrets.enc.yaml, both of which are often used in conjunction with SOPS.

Resolves #81

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• To see the specific tasks where the Asana app for GitHub is being used, see below:
  • https://app.asana.com/0/0/1209639515706677

[CharlieDixon]

Tested locally and is working as expected.

To replicate, install the Helm chart to a cluster, passing in an additional secrets manifest which matches the wildcard syntax included in these changes. For example:

helm install . -f  /path/to/lightdash-secrets.yaml.encrypted --generate-name -n lightdash`.

The checksum/secrets value will look something like this:

Annotations: checksum/config: 3d43a82693a770f503798e4474b0025d484b6111738d56049a26318fff32ad46
             checksum/secrets: 078bf8c86f91c1624faafbf55382d1a021f95fbd051616130bbc0644cf217db7

Next, make an arbitrary change to the content of either the default secrets.yaml or, in the example above,lightdash-secrets.yaml.encrypted values and perform an upgrade:

helm upgrade [CHART] . -f /path/to/lightdash-secrets.encrypted -n lightdash

N.B. The checksum generated for the ConfigMap remains the same but the secrets checksum has been updated in response to the changes which triggers a rolling restart of the deployment:

Annotations: checksum/config: 3d43a82693a770f503798e4474b0025d484b6111738d56049a26318fff32ad46
             checksum/secrets: 69b15bbe794142ea854bb7c04ae3f6ec71c263c038df5426c54caf076faea202