KeyError: key v"0.1.1" not found

I am trying to run this on Invenia's internal registry,
and I am getting an error:

```
julia> add_caps(MonotonicUpperBound(), CapLatestVersion(), ["General", "Invenia"])

ERROR: KeyError: key v"0.1.1" not found
Stacktrace:
[1] getindex
@ ./dict.jl:482 [inlined]
[2] add_caps
@ ~/.julia/packages/RetroCap/PhnbK/src/add_caps.jl:128 [inlined]
[3] add_caps
@ ~/.julia/packages/RetroCap/PhnbK/src/add_caps.jl:54 [inlined]
[4] add_caps(strategy::MonotonicUpperBound, option::CapLatestVersion, registry_paths::Vector{String})
@ RetroCap ~/.julia/packages/RetroCap/PhnbK/src/add_caps.jl:31
[5] top-level scope
@ REPL[14]:1
```

It is unclear what it is about, or how to fix it.
I suspect something at some point has been done to Invenia's registry that puts it in some kind of inconsistent state.