Update codecov setup to match datalad-core

Fixes datalad/datalad-extension-template#24

.appveyor.yml

@@ -67,6 +67,7 @@ environment:
       INSTALL_SYSPKGS: python3-virtualenv
       # system git-annex is way too old, use better one
       INSTALL_GITANNEX: git-annex -m deb-url --url http://snapshot.debian.org/archive/debian/20210906T204127Z/pool/main/g/git-annex/git-annex_8.20210903-1_amd64.deb
+      CODECOV_BINARY: https://uploader.codecov.io/latest/linux/codecov
     # Windows core tests
     - ID: WinP39core
       # ~35 min
@@ -82,6 +83,7 @@ environment:
       PY: 3.8
       INSTALL_GITANNEX: git-annex
       DATALAD_LOCATIONS_SOCKETS: /Users/appveyor/DLTMP/sockets
+      CODECOV_BINARY: https://uploader.codecov.io/latest/macos/codecov
 
 matrix:
   allow_failures:
@@ -189,15 +191,12 @@ test_script:
 
 
 after_test:
-  # move coverage into the project dir to make default handling applicable
-  - cmd: move .coverage ..
-  - sh: mv .coverage ..
-  - cd ..
-  # use windows codecov uploader package
-  - cmd: choco install codecov
-  - cmd: python -m coverage xml
-  - cmd: codecov -f coverage.xml
-  - sh: bash <(curl -sfS https://codecov.io/bash)
+  - python -m coverage xml
+  - cmd: curl -fsSL -o codecov.exe "https://uploader.codecov.io/latest/windows/codecov.exe"
+  - cmd: .\codecov.exe -f "coverage.xml"
+  - sh: "curl -Os $CODECOV_BINARY"
+  - sh: chmod +x codecov
+  - sh: ./codecov
 
 
 #on_success: