ios: pin distribution signing identity

ios/.env.example

@@ -5,6 +5,7 @@ FASTLANE_HIDE_CHANGELOG=1
 SYBIL_APP_STORE_APPLE_ID=6759442828
 SYBIL_PROVIDER_PUBLIC_ID=c043d167-ad88-4036-84ea-76c223f1b1b2
 SYBIL_PROVISIONING_PROFILE_SPECIFIER=Sybil AppStore CI
+SYBIL_CODE_SIGN_IDENTITY=Apple Distribution: James Magahern (DQQH5H6GBD)
 SYBIL_SIGNING_CERTIFICATE_ID=
 SYBIL_SIGNING_KEYCHAIN=
 

ios/fastlane/Fastfile

@@ -19,6 +19,7 @@ TEAM_ID = ENV.fetch("FASTLANE_TEAM_ID", "DQQH5H6GBD")
 APP_STORE_APPLE_ID = ENV.fetch("SYBIL_APP_STORE_APPLE_ID", "6759442828")
 PROVIDER_PUBLIC_ID = ENV.fetch("SYBIL_PROVIDER_PUBLIC_ID", "c043d167-ad88-4036-84ea-76c223f1b1b2")
 PROFILE_SPECIFIER = ENV["SYBIL_PROVISIONING_PROFILE_SPECIFIER"].to_s.strip.empty? ? "Sybil AppStore CI" : ENV["SYBIL_PROVISIONING_PROFILE_SPECIFIER"]
+SIGNING_CERTIFICATE_NAME = ENV["SYBIL_CODE_SIGN_IDENTITY"].to_s.strip.empty? ? "Apple Distribution: James Magahern (DQQH5H6GBD)" : ENV["SYBIL_CODE_SIGN_IDENTITY"]
 IOS_ROOT = File.expand_path("..", __dir__)
 PROJECT_FILE = File.join(IOS_ROOT, "Sybil.xcodeproj")
 PROJECT_SPEC = File.join(IOS_ROOT, "project.yml")
@@ -347,7 +348,7 @@ platform :ios do
       xcode_build_setting("CODE_SIGN_STYLE", "Manual"),
       xcode_build_setting("DEVELOPMENT_TEAM", TEAM_ID),
       xcode_build_setting("PROVISIONING_PROFILE_SPECIFIER", PROFILE_SPECIFIER),
-      xcode_build_setting("CODE_SIGN_IDENTITY", "Apple Distribution")
+      xcode_build_setting("CODE_SIGN_IDENTITY", SIGNING_CERTIFICATE_NAME)
     ].join(" ")
 
     ipa_path = build_app(
@@ -366,6 +367,7 @@ platform :ios do
         provisioningProfiles: {
           APP_IDENTIFIER => PROFILE_SPECIFIER
         },
+        signingCertificate: SIGNING_CERTIFICATE_NAME,
         teamID: TEAM_ID,
         manageAppVersionAndBuildNumber: false,
         uploadSymbols: true,