[Java] FR/suggestion/feedback: exclude Intellicode extention, enable granularity for extensions and what about the gradle extension?

Hi.

Currently the java feature includes the `Extension Pack for Java` (`vscjava.vscode-java-pack`) extension as part of the feature. This extension currently includes the following:

- `Language Support for Java(TM) by Red Hat` (`redhat.java`)
- `Debugger for Java` (`vscjava.vscode-java-debug`)
- `Test Runner for Java` (`vscjava.vscode-java-test`)
- `Maven for Java` (`vscjava.vscode-maven`)
- `Project Manager for Java` (`vscjava.vscode-java-dependency`)
- `IntelliCode` (`VisualStudioExptTeam.vscodeintellicode`)
- which in turn includes `Intellicode API Usage Examples` (`visualstudioexptteam.intellicode-api-usage-examples`)

Personally, I do not want any of that AI stuff force fed and would much appreciate it if it was not installed via the feature by default.

If I choose Gradle over Maven as the build tool, the Maven extension (`vscjava.vscode-maven`) is still installed but not the Gradle (`vscjava.vscode-gradle`) one, should that not at least be consistent?

Also, I do not understand the reasoning behind installing ESlint (`dbaeumer.vscode-eslint`) in the feature by default.

Now, I am aware of the recent addition to `vscode-remote` allowing for [opting out of installing](https://github.com/microsoft/vscode-docs/blob/main/remote-release-notes/v1_85.md#opt-out-of-extensions) extensions via the devcontainers definition but that is really just a band aid attempting to fix the symptom rather than a fix for the cause. If I choose to use the opt out feature, I need to manually exclude the Java pack (and the eslinting stuff) and manually add all but the Intellicode extension

This is how the devcontainer definition is going to look like:
```json

"customizations": {
"vscode": {
"extensions": [
"-dbaeumer.vscode-eslint",
"-vscjava.vscode-java-pack",
"-vscjava.vscode-maven",
"-visualstudioexptteam.intellicode-api-usage-examples",
"-visualstudioexptteam.vscodeintellicode",

"redhat.java",
"vscjava.vscode-java-dependency",
"vscjava.vscode-java-test",
"vscjava.vscode-java-debug",
"vscjava.vscode-gradle",
]
}
```

which is just stupid.

Perhaps what really need to happen is a conversation about increased granularity related to the extensions as well as consistency between the selected build tool an the installed extensions.