Cygwin: Remove .drone.yml

tea-ci.org was a CI service for MSYS2, but is no longer operating.

.drone.yml

@@ -1,58 +0,0 @@
-# Build configuration for https://tea-ci.org
-# Tea CI is a fork of Drone CI with Cygwin/Msys2 support
-# Feel free to share Tea CI to more open source developers
-# https://docs.tea-ci.org/usage/overview/
-
-debug: true
-
-build:
-  stage1:
-    image: teaci/cygwin$$arch
-    pull: true
-    shell: cygwin$$arch
-    commands:
-      - uname -a
-      - id
-      - C:/cygwin-installer.exe --site http://mirrors.tea-ci.org/cygwin --local-package-dir Z:/tmp/cygwin -W -P gettext-devel,zlib-devel,libiconv,libiconv-devel,mingw64-i686-gcc-g++,mingw64-i686-zlib,mingw64-x86_64-gcc-core,mingw64-x86_64-gcc-g++,mingw64-x86_64-zlib,dejagnu,dblatex,docbook-xml45,docbook-xsl,xmlto -q &> /dev/null
-      - srcdir=`pwd`
-      - builddir=/oss/build-stage1
-      - installdir=/oss/install-stage1
-      - mkdir -p ${builddir} ${installdir}
-      - cd ${builddir}
-      - ${srcdir}/configure --prefix=${installdir} -v
-      - make
-      - make install
-      - sha1sum ${installdir}/bin/cygwin1.dll /bin/cygwin1.dll
-      # FIXME: Is there an easy way to package new Cygwin then install locally using setup_x86{,-64}.exe?
-      - cp -vf ${installdir}/bin/cygwin1.dll /bin/cygwin1.dll
-
-  test:
-    image: teaci/cygwin$$arch
-    pull: true
-    shell: /bin/bash # Call from Linux native shell, which is a special bonus of Tea CI.
-    commands:
-      # In the worst case, new cygwin1.dll might fail to start with exit status 0, which fools the CI as status success.
-      # The following test does not rely on cygwin exit status, instead we trust Linux grep result.
-      - cygwin$$arch -c "uname -a" | grep CYGWIN_NT
-      - cygwin$$arch -c "id" | grep uid
-      - cygwin$$arch -c "sha1sum --tag /bin/cygwin1.dll" | grep SHA1
-
-  # Compile Cygwin again using the new cygwin1.dll
-  stage2:
-    image: teaci/cygwin$$arch
-    pull: true
-    shell: cygwin$$arch
-    commands:
-      - srcdir=`pwd`
-      - builddir=/oss/build-stage2
-      - installdir=/oss/install-stage2
-      - mkdir -p ${builddir} ${installdir}
-      - cd ${builddir}
-      - ${srcdir}/configure --prefix=${installdir} -v
-      - make
-      - make install
-
-matrix:
-  arch:
-    - 64
-    - 32