Add session reducer tests (#3860)

package.json

@@ -290,7 +290,7 @@
       "\\.[jt]sx?$": "babel-jest"
     },
     "transformIgnorePatterns": [
-      "node_modules/(?!((jest-)?react-native|@react-native(-community)?)|expo(nent)?|@expo(nent)?/.*|@expo-google-fonts/.*|react-navigation|nanoid|@react-navigation/.*|@unimodules/.*|unimodules|sentry-expo|native-base|normalize-url|react-native-svg|@sentry/.*|sentry-expo|bcp-47-match)"
+      "node_modules/(?!((jest-)?react-native|@react-native(-community)?)|@discord|expo(nent)?|@expo(nent)?/.*|@expo-google-fonts/.*|react-navigation|nanoid|@react-navigation/.*|@unimodules/.*|unimodules|sentry-expo|native-base|normalize-url|react-native-svg|@sentry/.*|sentry-expo|bcp-47-match)"
     ],
     "modulePathIgnorePatterns": [
       "__tests__/.*/__mocks__",

src/state/session/reducer.ts

@@ -6,6 +6,7 @@ import {SessionAccount} from './types'
 // A hack so that the reducer can't read anything from the agent.
 // From the reducer's point of view, it should be a completely opaque object.
 type OpaqueBskyAgent = {
+  readonly service: URL
   readonly api: unknown
   readonly app: unknown
   readonly com: unknown