Update Privacy Policy Link to GitHub.io (commons-app#6255)

* "moved privacy policy"

* Update PRIVACY_POLICY_URL to https://commons-app.github.io/privacy-policy as suggested

* Use BuildConfig.PRIVACY_POLICY_URL in launchPrivacyPolicy function

Author: sonalyadav1

app/build.gradle

@@ -318,7 +318,7 @@ android {
             buildConfigField "String", "SIGNUP_LANDING_URL", "\"https://commons.m.wikimedia.org/w/index.php?title=Special:CreateAccount&returnto=Main+Page&returntoquery=welcome%3Dyes\""
             buildConfigField "String", "SIGNUP_SUCCESS_REDIRECTION_URL", "\"https://commons.m.wikimedia.org/w/index.php?title=Main_Page&welcome=yes\""
             buildConfigField "String", "FORGOT_PASSWORD_URL", "\"https://commons.wikimedia.org/wiki/Special:PasswordReset\""
-            buildConfigField "String", "PRIVACY_POLICY_URL", "\"https://github.com/commons-app/commons-app-documentation/blob/master/android/Privacy-policy.md\""
+            buildConfigField "String", "PRIVACY_POLICY_URL", "\"https://commons-app.github.io/privacy-policy\""
             buildConfigField "String", "FILE_USAGES_BASE_URL", "\"https://commons.wikimedia.org/w/api.php?action=query&format=json&formatversion=2\""
             buildConfigField "String", "ACCOUNT_TYPE", "\"fr.free.nrw.commons\""
             buildConfigField "String", "CONTRIBUTION_AUTHORITY", "\"fr.free.nrw.commons.contributions.contentprovider\""
@@ -355,7 +355,7 @@ android {
             buildConfigField "String", "SIGNUP_LANDING_URL", "\"https://commons.m.wikimedia.beta.wmflabs.org/w/index.php?title=Special:CreateAccount&returnto=Main+Page&returntoquery=welcome%3Dyes\""
             buildConfigField "String", "SIGNUP_SUCCESS_REDIRECTION_URL", "\"https://commons.m.wikimedia.beta.wmflabs.org/w/index.php?title=Main_Page&welcome=yes\""
             buildConfigField "String", "FORGOT_PASSWORD_URL", "\"https://commons.wikimedia.beta.wmflabs.org/wiki/Special:PasswordReset\""
-            buildConfigField "String", "PRIVACY_POLICY_URL", "\"https://github.com/commons-app/commons-app-documentation/blob/master/android/Privacy-policy.md\""
+            buildConfigField "String", "PRIVACY_POLICY_URL", "\"https://commons-app.github.io/privacy-policy\""
             buildConfigField "String", "FILE_USAGES_BASE_URL", "\"https://commons.wikimedia.org/w/api.php?action=query&format=json&formatversion=2\""
             buildConfigField "String", "ACCOUNT_TYPE", "\"fr.free.nrw.commons.beta\""
             buildConfigField "String", "CONTRIBUTION_AUTHORITY", "\"fr.free.nrw.commons.beta.contributions.contentprovider\""