[BUG][Typescript-axios] The context of `this` is lost when dereferencing a class method

Hi folks, I ran in an issue when attempting to add a wrapper function to my api calls with the class api. We access this.configuration, but this is undefined when attempting to call the function

Example:

const api = new PetApi(undefined);

function logWrapper <T extends unknown[], U> (fn: (...args: T) => U, ...args: T) {
    console.log("Calling api with args: ", args);
    // `this` is undefined in this call
    return fn(...args);
}

logWrapper(api.getPetById, 1).then((result) => {
    console.log("Result: ", result);
});

I added a test case that reproduces the bug, and type annotations for the other apis that do not reference this for eslint.

References:

Technical Committee:

@TiFu (2017/07) @taxpon (2017/07) @sebastianhaas (2017/07) @kenisteward (2017/07) @Vrolijkx (2017/09) @macjohnny (2018/01) @topce (2018/10) @akehir (2019/07) @petejohansonxo (2019/11) @amakhrov (2020/02) @davidgamero (2022/03) @mkusaka (2022/04)

PR checklist

[x] Read the contribution guidelines.
[x] Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
[x] Run the following to build the project and update samples:
```
./mvnw clean package 
./bin/generate-samples.sh ./bin/configs/*.yaml
./bin/utils/export_docs_generators.sh
```
(For Windows users, please run the script in Git BASH) Commit all changed files. This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master. These must match the expectations made by your contribution. You may regenerate an individual generator by passing the relevant config(s) as an argument to the script, for example ./bin/generate-samples.sh bin/configs/java*. IMPORTANT: Do NOT purge/delete any folders/files (e.g. tests) when regenerating the samples as manually written tests may be removed.
[x] File the PR against the correct branch: master (upcoming 7.6.0 minor release - breaking changes with fallbacks), 8.0.x (breaking changes without fallbacks)
[x] If your PR is targeting a particular programming language, @mention the technical committee members, so they are more likely to review the pull request.

OpenAPITools / openapi-generator