Test suite is not re-runnable using `--watch` due to keeping state

[Carl-Erik Kopseng]

Describe the bug
When using the --watch option of Mocha the tests start failing on any change

To Reproduce
Steps to reproduce the behavior:

1. npx mocha --watch test
2. Change any test file
3. See the test suite break with 4 failing tests

 1259 passing (3s)
  2 pending
  4 failing

  1) assert
       message
         assert.calledWith match.defined exception message:

      AssertionError: [assert.equals] 'expected doSomething to be called with arguments \n \x1B[31m\x1B[31mdefined\x1B[0m\x1B[0m' expected to be equal to 'expected doSomething to be called with arguments \n \x1B[31mdefined\x1B[0m'
      + expected - actual

       expected doSomething to be called with arguments 
      - defined
      + defined
      
      at Object.fail (node_modules/@sinonjs/referee/lib/create-fail.js:5:21)
      at Object.fail (node_modules/@sinonjs/referee/lib/define-assertion/index.js:47:17)
      at assertion (node_modules/@sinonjs/referee/lib/define-assertion/index.js:65:11)
      at Function.referee.<computed>.<computed> [as equals] (node_modules/@sinonjs/referee/lib/define-assertion/index.js:92:22)
      at Context.<anonymous> (test/assert-test.js:1847:20)
      at processImmediate (node:internal/timers:466:21)

  2) assert
       message
         assert.calledWith match.truthy exception message:

      AssertionError: [assert.equals] 'expected doSomething to be called with arguments \n \x1B[31m\x1B[31mtruthy\x1B[0m\x1B[0m' expected to be equal to 'expected doSomething to be called with arguments \n \x1B[31mtruthy\x1B[0m'
      + expected - actual

       expected doSomething to be called with arguments 
      - truthy
      + truthy
      
      at Object.fail (node_modules/@sinonjs/referee/lib/create-fail.js:5:21)
      at Object.fail (node_modules/@sinonjs/referee/lib/define-assertion/index.js:47:17)
      at assertion (node_modules/@sinonjs/referee/lib/define-assertion/index.js:65:11)
      at Function.referee.<computed>.<computed> [as equals] (node_modules/@sinonjs/referee/lib/define-assertion/index.js:92:22)
      at Context.<anonymous> (test/assert-test.js:1858:20)
      at processImmediate (node:internal/timers:466:21)

  3) assert
       message
         assert.calledWith match.falsy exception message:

      AssertionError: [assert.equals] 'expected doSomething to be called with arguments \n' +
  '\x1B[32mtrue\x1B[0m \x1B[31m\x1B[31mfalsy\x1B[0m\x1B[0m' expected to be equal to 'expected doSomething to be called with arguments \n' +
  '\x1B[32mtrue\x1B[0m \x1B[31mfalsy\x1B[0m'
      + expected - actual

       expected doSomething to be called with arguments 
      -true falsy
      +true falsy
      
      at Object.fail (node_modules/@sinonjs/referee/lib/create-fail.js:5:21)
      at Object.fail (node_modules/@sinonjs/referee/lib/define-assertion/index.js:47:17)
      at assertion (node_modules/@sinonjs/referee/lib/define-assertion/index.js:65:11)
      at Function.referee.<computed>.<computed> [as equals] (node_modules/@sinonjs/referee/lib/define-assertion/index.js:92:22)
      at Context.<anonymous> (test/assert-test.js:1869:20)
      at processImmediate (node:internal/timers:466:21)

  4) stub
       non enumerable properties
         create stub from function on object:

      AssertionError: [assert.equals] [ 'aProp', 'func2' ] expected to be equal to [ 'aProp' ]
      + expected - actual

       [
         "aProp"
      -  "func2"
       ]
      
      at Object.fail (node_modules/@sinonjs/referee/lib/create-fail.js:5:21)
      at Object.fail (node_modules/@sinonjs/referee/lib/define-assertion/index.js:47:17)
      at assertion (node_modules/@sinonjs/referee/lib/define-assertion/index.js:65:11)
      at Function.referee.<computed>.<computed> [as equals] (node_modules/@sinonjs/referee/lib/define-assertion/index.js:92:22)
      at Context.<anonymous> (test/stub-test.js:180:20)
      at processImmediate (node:internal/timers:466:21)

Expected behavior
Immutable, non-failing test runs with no shared global state.

Context (please complete the following information):

• Library version: 15.0.2

Additional context

This is due to two things that I could see

1. We change the prototype of Function in https://github.com/sinonjs/sinon/pull/1968/files#diff-ebffa5a039be75d22925d266e16de1f0dbf14a625e5998bb0982e8523ce791c9R1332-R1337
2. Some tests seem to keep state that makes re-runs of tests fail

[Carl-Erik Kopseng]

Was closed in #2504