ci/request-reviews: Don't rerequest users that already reviewed

The automation should never rerequest reviews from users that already
reviewed the changes, which is what was happening before this change:

#347354 (comment)

Also reorder the arguments to make more sense

(cherry picked from commit 9a054bb)

ci/request-reviews/get-reviewers.sh

@@ -10,16 +10,18 @@ log() {
     echo "$@" >&2
 }
 
-if (( "$#" < 5 )); then
-    log "Usage: $0 GIT_REPO BASE_REF HEAD_REF OWNERS_FILE PR_AUTHOR"
+if (( "$#" < 7 )); then
+    log "Usage: $0 GIT_REPO OWNERS_FILE BASE_REPO BASE_REF HEAD_REF PR_NUMBER PR_AUTHOR"
     exit 1
 fi
 
 gitRepo=$1
-baseRef=$2
-headRef=$3
-ownersFile=$4
-prAuthor=$5
+ownersFile=$2
+baseRepo=$3
+baseRef=$4
+headRef=$5
+prNumber=$6
+prAuthor=$7
 
 tmp=$(mktemp -d)
 trap 'rm -rf "$tmp"' exit
@@ -77,6 +79,20 @@ if [[ -v users[$prAuthor] ]]; then
     unset 'users[$prAuthor]'
 fi
 
+gh api \
+    -H "Accept: application/vnd.github+json" \
+    -H "X-GitHub-Api-Version: 2022-11-28" \
+    "/repos/$baseRepo/pulls/$prNumber/reviews" \
+    --jq '.[].user.login' > "$tmp/already-reviewed-by"
+
+# And we don't want to rerequest reviews from people who already reviewed
+while read -r user; do
+    if [[ -v users[$user] ]]; then
+        log "User $user is a code owner but has already left a review, ignoring"
+        unset 'users[$user]'
+    fi
+done < "$tmp/already-reviewed-by"
+
 # Turn it into a JSON for the GitHub API call to request PR reviewers
 jq -n \
     --arg users "${!users[*]}" \

ci/request-reviews/request-reviews.sh

@@ -80,7 +80,7 @@ if ! "$SCRIPT_DIR"/verify-base-branch.sh "$tmp/nixpkgs.git" "$headRef" "$baseRep
 fi
 
 log "Getting code owners to request reviews from"
-"$SCRIPT_DIR"/get-reviewers.sh "$tmp/nixpkgs.git" "$baseBranch" "$headRef" "$ownersFile" "$prAuthor" > "$tmp/reviewers.json"
+"$SCRIPT_DIR"/get-reviewers.sh "$tmp/nixpkgs.git" "$ownersFile" "$baseRepo" "$baseBranch" "$headRef" "$prNumber" "$prAuthor" > "$tmp/reviewers.json"
 
 log "Requesting reviews from: $(<"$tmp/reviewers.json")"