--reuse-values causes diff rendering failure on initial install

[michaelsauter]

When installing ODS Pipeline, the following is printed:

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        Release was not present in Helm.  Diff will show entire contents as new.

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Error: Failed to render chart: exit status 1

However, the actual installation is done properly as it should.

It seems that using --reuse-values when there is no release causes the error Failed to render chart. Without --reuse-values, the diff is printed as expected (showing everything as to be added).

The error should not be printed during installation in order to avoid confusion and allow users to visually inspect the manifest being installed.