fix: remove unsupported android platform from .spi.yml

'android' is not a valid Swift Package Index build platform.
SPI validates the manifest schema before processing — an unknown
platform entry causes the entire file to be rejected, preventing
SPI from picking up new releases.

Also removed the malformed 'swift_version' (singular) key that
appeared in the android entry; the correct key is 'swift_versions'.

Valid SPI platforms: macos-spm, linux, ios, tvos, watchos, visionos.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: vkuttyp

.spi.yml

@@ -17,5 +17,3 @@ builder:
       linux_packages:
         - libsqlite3-dev
         - pkg-config
-    - platform: android
-      swift_version: "6.0"