Two-temperature-plasma incompatible with third-body notation

[ischoegl]

Problem description

Per #967/#1015/#1027 the following reaction in test/data/ET_test.yaml

- equation: E + O2 + O2 => O2^- + O2  # Kossyi (1992) Eq.45
  type: two-temperature-plasma
  rate-constant: {A: 1.523e+27, b: -1.0, Ea_T: -100, Ea_Te: 700}

is a three-body reaction, but is currently not handled as such.

Steps to reproduce

Found in #1219

Behavior

Reaction was found using a generic search for implicitly defined third-body colliders

System information

• Cantera version: [for example, 2.5.0 or the git commit hash] 2.6.0a4
• OS: [for example, Windows 10]
• Python/MATLAB/other software versions: