test: add ignoreUpstreamProxyCertificate tests (#583)

* add ignoreUpstreamProxyCertificate tests

* 2.5.9

* rename the test group to use whole correct option name

* Add comments with explanations to the new tests

Add HTTPS upstream proxy support with option to ignore proxy cert err…

…ors (#577)

This PR adds support for a new boolean option `ignoreProxyCertificate`. If set to `true`, certificate errors will be ignored, which can be useful for HTTPS proxies with self-signed certificates.

Usage:

```
const server = new Server({
  prepareRequestFunction: () => ({
    upstreamProxyUrl: 'https://user:pass@myproxy:8080',
    ignoreUpstreamProxyCertificate: true  // Useful for self-signed cert
  })
}).listen();
```
Anonymize:
```
anonymizeProxy({
  url: 'https://user:pass@myproxy:8080',
  ignoreProxyCertificate: true,
}).then((anonymizedURL) => {
  console.log(`Anonymized URL: ${anonymizedURL}`);
});
```
Create tunnel:
```
createTunnel(
  'https://user:pass@myproxy:8080',
  targetHost,
  { ignoreProxyCertificate: true }
).then((url) => {
  console.log('Tunnel endpoint:', url);
});
```

Add HTTPS upstream proxy support with option to ignore proxy cert err…

…ors (#577)

This PR adds support for a new boolean option `ignoreProxyCertificate`. If set to `true`, certificate errors will be ignored, which can be useful for HTTPS proxies with self-signed certificates.

Usage:

```
const server = new Server({
  prepareRequestFunction: () => ({
    upstreamProxyUrl: 'https://user:pass@myproxy:8080',
    ignoreUpstreamProxyCertificate: true  // Useful for self-signed cert
  })
}).listen();
```
Anonymize:
```
anonymizeProxy({
  url: 'https://user:pass@myproxy:8080',
  ignoreProxyCertificate: true,
}).then((anonymizedURL) => {
  console.log(`Anonymized URL: ${anonymizedURL}`);
});
```
Create tunnel:
```
createTunnel(
  'https://user:pass@myproxy:8080',
  targetHost,
  { ignoreProxyCertificate: true }
).then((url) => {
  console.log('Tunnel endpoint:', url);
});
```

chore: update shared eslint config to a stable version (#579)

fix: correct target stats when sockets are reused (#576)

This PR attempts to fix incorrect stats due to the reuse of target sockets for HTTP(S) protocols. 

Based on #572

Note: I was forced to upgrade `actions/cache` as `v2` was deprecated and it wouldn't run with it.
I also had to edit eslint config to run with `.` instead of `src` and excluded `tests`, because with `src` the CI was failing (no idea why).

fix: correct target stats when sockets are reused (#576)

This PR attempts to fix incorrect stats due to the reuse of target sockets for HTTP(S) protocols. 

Based on #572

Note: I was forced to upgrade `actions/cache` as `v2` was deprecated and it wouldn't run with it.
I also had to edit eslint config to run with `.` instead of `src` and excluded `tests`, because with `src` the CI was failing (no idea why).

docs: update report the port (#573)

fixed missing log prefix for the first request (#571)

chore: update eslint to v9, use new shared config (#568)

chore: bump package version (#566)