pyciemss.sample throws error when the initial condition expressions contain just an integer

[liunelson]

This bug occurs when the AMR initials expressions are all strings containing just an integer.
For example (SIR (integers).json):

      "initials": [
        {
          "target": "R",
          "expression": "0",
          "expression_mathml": "<math></math>"
        },
        {
          "target": "I",
          "expression": "1",
          "expression_mathml": "<math></math>"
        },
        {
          "target": "S",
          "expression": "100",
          "expression_mathml": "<math></math>"
        }
      ]

No error is thrown if one appends a .0 to each of the expressions (SIR (floats).json).

SIR (floats).json
SIR (integers).json

[liunelson]

I recreated the issue from the Terarium repo to here for tracking.