Disables extension auto-reload when saving files (isaac-sim#1788)

# Description

Since extensions are now added to the app files, they get automatically
reloaded when changes happen in the extension scripts. This feature is
most likely not useful for Isaac Lab development workflows. This change
disables the hot reload feature as it causes confusion and unnecessary
reloading of the modules.

Fixes isaac-sim#1779 

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## Type of change

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applicable. -->

- Bug fix (non-breaking change which fixes an issue)

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [x] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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Co-authored-by: Mayank Mittal <[email protected]>

Author: kellyguo11

source/isaaclab/config/extension.toml

@@ -32,5 +32,8 @@ modules = [
 
 use_online_index=true
 
+[core]
+reloadable = false
+
 [[python.module]]
 name = "isaaclab"

source/isaaclab_assets/config/extension.toml

@@ -13,6 +13,9 @@ keywords = ["kit", "robotics", "assets", "isaaclab"]
 [dependencies]
 "isaaclab" = {}
 
+[core]
+reloadable = false
+
 # Main python module this extension provides.
 [[python.module]]
 name = "isaaclab_assets"

source/isaaclab_mimic/config/extension.toml

@@ -20,6 +20,9 @@ keywords = ["extension", "template", "isaaclab"]
 "isaaclab_tasks" = {}
 # NOTE: Add additional dependencies here
 
+[core]
+reloadable = false
+
 [[python.module]]
 name = "isaaclab_mimic"
 

source/isaaclab_rl/config/extension.toml

@@ -16,5 +16,8 @@ keywords = ["robotics", "rl", "wrappers", "learning"]
 "isaaclab_assets" = {}
 "isaaclab_tasks" = {}
 
+[core]
+reloadable = false
+
 [[python.module]]
 name = "isaaclab_rl"

source/isaaclab_tasks/config/extension.toml

@@ -15,5 +15,8 @@ keywords = ["robotics", "rl", "il", "learning"]
 "isaaclab" = {}
 "isaaclab_assets" = {}
 
+[core]
+reloadable = false
+
 [[python.module]]
 name = "isaaclab_tasks"