[mob][auth] Add certificate fingerprint (#4632)

## Description

## Tests

Author: ua741

auth/README.md

@@ -100,6 +100,16 @@ Photos](../mobile/README.md) or spreading the word.
 
 For more ways to contribute, see [../CONTRIBUTING.md](../CONTRIBUTING.md).
 
+## Certificate Fingerprints
+
+- **SHA1**: 57:E8:C6:59:C3:AA:C9:38:B0:10:70:5E:90:85:BC:20:67:E6:8F:4B
+- **SHA256**: BA:8B:F0:32:98:62:70:05:ED:DF:F6:B1:D6:0B:3B:FA:A1:4E:E8:BD:C7:61:4F:FB:3B:B1:1C:58:8D:9E:3A:D7
+
+To verify these fingerprints, use the following command:
+```bash
+apksigner verify --print-certs <path_to_apk>
+```
+
 ## ⭐️ About
 
 To know more about Ente and the ways to get in touch or seek help, see [our main

mobile/README.md

@@ -87,6 +87,16 @@ If your language is not listed for translation, please [create a GitHub
 issue](https://github.com/ente-io/ente/issues/new?title=Request+for+New+Language+Translation&body=Language+name%3A)
 to have it added.
 
+## Certificate Fingerprints
+ 
+- **SHA1**: E1:60:10:18:B6:B0:2E:A3:74:6F:90:67:50:30:29:75:0E:EF:6D:39
+- **SHA256**: 35:ED:56:81:B7:0B:B3:BD:35:D9:0D:85:6A:F5:69:4C:50:4D:EF:46:AA:D8:3F:77:7B:1C:67:5C:F4:51:35:0B
+
+To verify these fingerprints, use the following command:
+```bash
+apksigner verify --print-certs <path_to_apk>
+```
+
 ## 💚 Contribute
 
 For more ways to contribute, see [../CONTRIBUTING.md](../CONTRIBUTING.md).