Multiple error handling

[YoungFaithful]

Multiple error handling of a spawned task is currently sub optimal:

• The first error returns a failed task, but breaks the WorkerUtilities
• The second error is just a runnable task.
  How could we assign the error to the task and finish the task?

julia -t 2
               _
   _       _ _(_)_     |  Documentation: https://docs.julialang.org
  (_)     | (_) (_)    |
   _ _   _| |_  __ _   |  Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 1.5.3 (2020-11-09)
 _/ |\__'_|_|_|\__'_|  |  Official https://julialang.org/ release
|__/                   |

julia> using WorkerUtilities

julia> WorkerUtilities.init()

julia> resp = WorkerUtilities.@spawn(sqrt(-1))
Task (failed) @0x00007f96267c5120
DomainError with -1.0:
sqrt will only return a complex result if called with a complex argument. Try sqrt(Complex(x)).
throw_complex_domainerror(::Symbol, ::Float64) at ./math.jl:33
sqrt at ./math.jl:573 [inlined]
sqrt(::Int64) at ./math.jl:599
(::var"#1#2")() at ./task.jl:112

julia> resp
Task (failed) @0x00007f96267c5120
DomainError with -1.0:
sqrt will only return a complex result if called with a complex argument. Try sqrt(Complex(x)).
throw_complex_domainerror(::Symbol, ::Float64) at ./math.jl:33
sqrt at ./math.jl:573 [inlined]
sqrt(::Int64) at ./math.jl:599
(::var"#1#2")() at ./task.jl:112

julia> resp = WorkerUtilities.@spawn(sqrt(-2))
# Takes forever...

[YoungFaithful]

It helps to rerun WorkerUtilities.init() when an error occurs.