[prometheus-thanos] Wrap all thanos additional args in quotes

[iemre]

What this PR does / why we need it:

This allows us to pass additional flags that have new line characters and/or quotation marks in them. One specific example of this is the "tracing.config" flag that takes a YAML string that may contain new line characters, spaces and quotation marks. When this is the case, the provided YAML gets broken and becomes invalid.

We did this for Thanos Querier previously in https://github.com/kiwigrid/helm-charts/pull/419. This PR does the same for all Thanos components that accept additional args.

Signed-off-by: Emre Kartoglu iemrek@gmail.com

Special notes for your reviewer:

• I have tested the changes in a private setup.
• Apologies I should probably have included this in the PR https://github.com/kiwigrid/helm-charts/pull/419

Checklist

[Place an '[x]' (no spaces) in all applicable fields. Please remove unrelated fields.]

• [x] DCO signed
• [x] Chart Version bumped (if the pr is an update to an existing chart)
• [x] Variables are documented in the README.md
• [x] Title of the PR starts with chart name (e.g. [fluentd-elasticsearch])

[iemre]

@monotek since you reviewed a similar PR previously I'm tagging you. Thanks!