Remove ignored paths for build workflow

Since we have mandatory status checks enabled for pull requests, this
previously caused this action to not run, in turn reporting “Expected —
Waiting for status to be reported” on any PR that only changes the
ignored files.

This change will likely lead to a minor increase in build volume.
However, considering the fraction of cases in which only those files are
changed, it should be negligible.

.github/workflows/build.yml

@@ -6,9 +6,6 @@ name: CI build
 
 on:
   push:
-    paths-ignore:
-    - 'src/main/asciidoc/**'
-    - 'readme.adoc'
 
 env:
   MAVEN_OPTS: -Xmx1G