Imports of modules that have current module name as prefix are dropped silently

[jespercockx]

If I have a module AAA that imports another module AAABBB, then this import is dropped from the generated Haskell code. The cause is located here: https://github.com/agda/agda2hs/blob/0fc20ccd031a07c848824fc125839b4d91e35667/src/Agda2Hs/Compile/Imports.hs#L28

(Git blame tells me I have no-one to blame except for myself.)