The two spaces at the start of every line in the _helpers.tpl file caused extra indentation in the resultant YAML file in unexpectated spaces, causing parsing errors. Removed.
The inclusion of .Values.env in deployment.yaml was done without checking for the existence of it first. In cases where env didn't exist, this would return the string null, which caused a parsing error. Added a conditional to check for the existence of .Values.env.
.Values.envin deployment.yaml was done without checking for the existence of it first. In cases where env didn't exist, this would return the stringnull, which caused a parsing error. Added a conditional to check for the existence of.Values.env.