Remove CI manifest

It hasn't been working for a while

.build.yml

@@ -1,26 +0,0 @@
----
-# we rsync binaries.tar.gz from the same server we deploy to.
-# it contains these static-pie binaries:
-# hugo, brotli, ect (like gzip/zopfli), and xmllint.
-image: alpine/edge
-packages:
-  - curl # Fetches webmentions and webring links. Pre-inistalled.
-  - rsync
-  - git  # Powers Hugo's gitInfo. Pre-installed
-  - bmake # gmake is fine too
-sources:
-  - https://git.sr.ht/~seirdy/seirdy.one
-secrets:
-  - cc1eb90c-b07b-4c46-86d4-58fec41cf0e4 # ssh key
-  - b0bfa66e-3cf2-468f-9ea4-085819eccd18 # webmentiond key
-triggers:
-  - action: email
-    condition: always
-    to: seirdy@seirdy.one
-tasks:
-  - deps: |
-      sh seirdy.one/scripts/setup-ci.sh
-  - build_deploy: |
-      export PATH=~/bin:$PATH
-      cd seirdy.one
-      bmake ci