ci: Eigen moved

Author: henryiii

.appveyor.yml

@@ -21,9 +21,9 @@ install:
     python -W ignore -m pip install --upgrade pip wheel
     python -W ignore -m pip install pytest numpy --no-warn-script-location
 - ps: |
-    Start-FileDownload 'http://bitbucket.org/eigen/eigen/get/3.3.3.zip'
-    7z x 3.3.3.zip -y > $null
-    $env:CMAKE_INCLUDE_PATH = "eigen-eigen-67e894c6cd8f;$env:CMAKE_INCLUDE_PATH"
+    Start-FileDownload 'https://gitlab.com/libeigen/eigen/-/archive/3.3.7/eigen-3.3.7.zip'
+    7z x eigen-3.3.7.zip -y > $null
+    $env:CMAKE_INCLUDE_PATH = "eigen-3.3.7;$env:CMAKE_INCLUDE_PATH"
 build_script:
 - cmake -G "%CMAKE_GENERATOR%" -A "%CMAKE_ARCH%"
     -DCMAKE_CXX_STANDARD=14