Use consistent capitalization in error messages

[AObuchow]

#1064 refactored the way errors were propagated in the devworkspace-controller, and highlighted the fact that some error messages in DWO start with a lower case letter while others start with a capital letter.

It would be nice to make the capitalization of error messages consistent, as they can be shown to the user in cases where the workspace startup fails.

Some things to consider:

• Do we want DW error & warning status messages to always start with a lower case letter, or upper case?
• Some error messages get concatenated with another error message to provide some context, so it's not just a matter of changing all error messages to start with an upper or lower case letter.
  • Maybe the functions set the workspace status messages (e.g. this one for failing workspaces) should automatically capitalize the first letter of the workspace status message. This way, we could more easily enforce the standard of all error messages starting with a lowercase letter while ensuring user-facing error messages start with an uppercase letter.

[Horiodino]

hey @AObuchow If no one else is currently working on this issue, I would like to take it on. Please let me know if it's available for me to handle.

[AObuchow]

@Horiodino no one is currently working on this issue, I'd be happy to have you work on it :)