Update submodules (#64)

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## Description
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Updates the library submodules.

NOTE: `minic` has a breaking change which required adding
`MINI_FLAGS_SKIP_EMPTY_GROUPS`. See:
6229658b9d

## Motivation and Context
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Keeps the project up-to-date

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## Types of changes
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the boxes that apply: -->
- [ ] Improvement (non-breaking change that adds a new feature)
- [ ] Bug fix (fixes an issue)
- [ ] Breaking change (breaking change)
- [x] Config and build (change in the configuration and build system,
has no impact on code or features)

## Checklist:
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- [ ] My code follows the code style of this project.
- [ ] My change requires a change to the documentation.
- [ ] I have updated the documentation accordingly.
- [ ] I have added tests to cover my changes.
- [ ] All new and existing tests passed.

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libdragon

@@ -1 +1 @@
-Subproject commit dd2202a6082cd3d92f4c22e64b27f148612c4c3a
+Subproject commit 4b38fd5618007e7ed9040107d0f7e52f2de81a22

src/libs/mini.c

@@ -1 +1 @@
-Subproject commit f713e3c98ee2340a90334da6084c34ec2109a7e6
+Subproject commit 6229658b9d275fb760bcee119104bdbd7873536e

src/libs/miniz

@@ -1 +1 @@
-Subproject commit 9ae305f6e109f8f1fbd2130458f1ee6197269b3b
+Subproject commit 18795fa61e590521381ba9e1fa4a4ab362b095f6

src/menu/settings.c

@@ -55,7 +55,7 @@ void settings_save (settings_t *settings) {
     // mini_set_bool(ini, "menu_beta_flag", "sound_enabled", init.sound_enabled);
     // mini_set_bool(ini, "menu_beta_flag", "rumble_enabled", init.rumble_enabled);
 
-    mini_save(ini);
+    mini_save(ini, MINI_FLAGS_SKIP_EMPTY_GROUPS);
 
     mini_free(ini);
 }