dotenv format in 3.6 is incompatible with version 3.5 #702
Description
After this change: #622
A dotenv file generated by 3.6.0 is not readable by SOPS 3.5 or earlier, because of the newly added single quotes around every value (which the old SOPS seems to be unable to parse). I'm not sure whether this kind of change should be considered a breaking change or not, but given a typical use case (where you encrypt in one place and decrypt in another place), it's certainly not uncommon for one side to be using a different version than the other, so it's definitely pseudo-breaking.
One potential solution is to remember whether the file had quotes or not, and don't add quotes to a file that didn't have quotes (unless some flag is passed). Another one might be a flag that can omit the dotenv quotes, like --omit-dotenv-quotes so that people running into this problem can at least generate a file in the old style without downgrading SOPS (it would be nice in this case if it were also a config setting in sops.yaml)