rockspec out of sync after #209 (popup integration)

[colemickens]

After #209, I get this:

@nix { "action": "setPhase", "phase": "unpackPhase" }
unpacking sources
unpacking source archive /nix/store/jbwlgm4fnb5kalgfhccqx60688lp86my-plenary.nvim-adf9d62
source root is plenary.nvim-adf9d62
@nix { "action": "setPhase", "phase": "patchPhase" }
patching sources
@nix { "action": "setPhase", "phase": "configurePhase" }
configuring
@nix { "action": "setPhase", "phase": "buildPhase" }
building
@nix { "action": "setPhase", "phase": "installPhase" }
installing

cp: cannot stat 'lua/plenary/popup.lua': No such file or directory

Error: Build error: Failed installing lua/plenary/popup.lua in /nix/store/dqa8ip5nc0g7z2dxccqf0ksfx035w1yz-lua5.1-plenary.nvim-scm-1/plenary.nvim-scm-1-rocks/plenary.nvim/scm-1/lua/plenary/popup.lua: Failed copying lua/plenary/popup.lua to /nix/store/dqa8ip5nc0g7z2dxccqf0ksfx035w1yz-lua5.1-plenary.nvim-scm-1/plenary.nvim-scm-1-rocks/plenary.nvim/scm-1/lua/plenary/popup.lua

Seems like the rockspec still references popup.lua instead of popup/init.lua.

[Conni2461]

Should be addressed in the last commit