Add simple live share warning (#8066)

* add simple live share warning

Signed-off-by: Kerry Archibald <kerrya@element.io>

* rough first cut of OwnBeaconStore

Signed-off-by: Kerry Archibald <kerrya@element.io>

* working (?) has live beacons status

Signed-off-by: Kerry Archibald <kerrya@element.io>

* lint

Signed-off-by: Kerry Archibald <kerrya@element.io>

* add left panel share warning

Signed-off-by: Kerry Archibald <kerrya@element.io>

* setup for tests

Signed-off-by: Kerry Archibald <kerrya@element.io>

* test ownbeaconstore

Signed-off-by: Kerry Archibald <kerrya@element.io>

* add copyright

Signed-off-by: Kerry Archibald <kerrya@element.io>

* add copyright

Signed-off-by: Kerry Archibald <kerrya@element.io>

* remove warning banner

Signed-off-by: Kerry Archibald <kerrya@element.io>

* fix test

Signed-off-by: Kerry Archibald <kerrya@element.io>

* fix tests for weird asyncstore closure issues

Signed-off-by: Kerry Archibald <kerrya@element.io>

* fix OwnBeaconStore more...

Signed-off-by: Kerry Archibald <kerrya@element.io>

* revert loose change to LeftPanel

Signed-off-by: Kerry Archibald <kerrya@element.io>

* Revert "remove warning banner"

This reverts commit 4529813b12e3206731f18e0514aa6e0f6896d03a.

* test live share warning

Signed-off-by: Kerry Archibald <kerrya@element.io>

src/i18n/strings/en_EN.json

@@ -2956,6 +2956,7 @@
     "Beta": "Beta",
     "Leave the beta": "Leave the beta",
     "Join the beta": "Join the beta",
+    "You are sharing your live location": "You are sharing your live location",
     "Avatar": "Avatar",
     "This room is public": "This room is public",
     "Away": "Away",