OpenAPI 3.x Go generation's weirdness for enum names

Currently, the enum names will be stripped the common prefixes.
If
```
- FORCE_COMPLETE_ON_INTERNAL_CHANNEL_EMPTY
- FORCE_COMPLETE_ON_SIGNAL_CHANNEL_EMPTY
```
Then the enum names are:
```
INTERNAL_CHANNEL_EMPTY
SIGNAL_CHANNEL_EMPTY
```
However, if
```
- FORCE_COMPLETE_ON_INTERNAL_CHANNEL_EMPTY
- FORCE_COMPLETE_ON_SIGNAL_CHANNEL_EMPTY
- GRACEFUL_COMPLETE_ON_ALL_CHANNELS_EMPTY
```
Then the enum names are
```
FORCE_COMPLETE_ON_INTERNAL_CHANNEL_EMPTY
FORCE_COMPLETE_ON_SIGNAL_CHANNEL_EMPTY
GRACEFUL_COMPLETE_ON_ALL_CHANNELS_EMPTY
```
Because they don't have the shared common prefix anymore. The generator is "trying to be smart" but it's a terrible idea to do this without any parameter to control.
This would be a problem because the enum names are unstable as adding different values.
It will be nice to somehow get rid of this "smart stripping"...

A workaround today is to use "enumClassPrefix=true" however, this is also a breaking change to all enum names, and also the enum names will be quite ugly...

Reported in https://github.com/OpenAPITools/openapi-generator/issues/16002

As a workaround today, make sure to have at least a letter different in all the enums from beginning...

The issue names no repository files or tests. Start by locating the OpenAPI 3.x Go-generation configuration and the schema containing the enum examples, then compare generated names with and without the third value. Done means enum names remain stable without requiring enumClassPrefix=true, with tests covering both value sets.

Written by the indexing model from the issue text.