Bump net-imap from 0.3.7 to 0.4.0 #1170

Job	Run time
Test Ruby	9m 26s
Lint Ruby / Run RuboCop	32s
Lint JavaScript / Run Standardx	15s
Lint SCSS / Run Stylelint	17s
Security Analysis / Run Brakeman	27s
Test JavaScript / Run Jasmine	1m 19s
	12m 16s

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