ci: add more ARM build configurations to CI and release workflows

... it turns out that rustembedded/cross:armv7-unknown-linux-musleabi
doesn't exist. And looking more closely, it looks like the Cross project
has decided to shake things up and publish images to ghcr instead. So we
migrate everything over to that.

tests/feature.rs

@@ -972,7 +972,7 @@ rgtest!(f1404_nothing_searched_warning, |dir: Dir, mut cmd: TestCommand| {
     cmd.assert_err();
 
     // Test that we actually get an error message that we expect.
-    let output = cmd.cmd().output().unwrap();
+    let output = cmd.raw_output();
     let stderr = String::from_utf8_lossy(&output.stderr);
     let expected = "\
         No files were searched, which means ripgrep probably applied \
@@ -995,7 +995,7 @@ rgtest!(f1404_nothing_searched_ignored, |dir: Dir, mut cmd: TestCommand| {
 
     // But since --no-messages is given, there should not be any error message
     // printed.
-    let output = cmd.cmd().output().unwrap();
+    let output = cmd.raw_output();
     let stderr = String::from_utf8_lossy(&output.stderr);
     let expected = "";
     eqnice!(expected, stderr);

tests/misc.rs

@@ -411,7 +411,7 @@ rgtest!(include_zero, |dir: Dir, mut cmd: TestCommand| {
     cmd.args(&["--count", "--include-zero", "nada"]);
     cmd.assert_err();
 
-    let output = cmd.cmd().output().unwrap();
+    let output = cmd.raw_output();
     let stdout = String::from_utf8_lossy(&output.stdout);
     let expected = "sherlock:0\n";
 
@@ -423,7 +423,7 @@ rgtest!(include_zero_override, |dir: Dir, mut cmd: TestCommand| {
     cmd.args(&["--count", "--include-zero", "--no-include-zero", "nada"]);
     cmd.assert_err();
 
-    let output = cmd.cmd().output().unwrap();
+    let output = cmd.raw_output();
     let stdout = String::from_utf8_lossy(&output.stdout);
     assert!(stdout.is_empty());
 });

tests/regression.rs

@@ -399,7 +399,7 @@ rgtest!(r428_unrecognized_style, |dir: Dir, mut cmd: TestCommand| {
     cmd.arg("--colors=match:style:").arg("Sherlock");
     cmd.assert_err();
 
-    let output = cmd.cmd().output().unwrap();
+    let output = cmd.raw_output();
     let stderr = String::from_utf8_lossy(&output.stderr);
     let expected = "\
 error parsing flag --colors: \

tests/util.rs

@@ -9,6 +9,8 @@ use std::sync::atomic::{AtomicUsize, Ordering};
 use std::thread;
 use std::time::Duration;
 
+use bstr::ByteSlice;
+
 static TEST_DIR: &'static str = "ripgrep-tests";
 static NEXT_ID: AtomicUsize = AtomicUsize::new(0);
 
@@ -325,13 +327,21 @@ impl TestCommand {
 
     /// Gets the output of a command. If the command failed, then this panics.
     pub fn output(&mut self) -> process::Output {
-        let output = self.cmd.output().unwrap();
+        let output = self.raw_output();
         self.expect_success(output)
     }
 
+    /// Gets the raw output of a command after filtering nonsense like jemalloc
+    /// error messages from stderr.
+    pub fn raw_output(&mut self) -> process::Output {
+        let mut output = self.cmd.output().unwrap();
+        output.stderr = strip_jemalloc_nonsense(&output.stderr);
+        output
+    }
+
     /// Runs the command and asserts that it resulted in an error exit code.
     pub fn assert_err(&mut self) {
-        let o = self.cmd.output().unwrap();
+        let o = self.raw_output();
         if o.status.success() {
             panic!(
                 "\n\n===== {:?} =====\n\
@@ -479,7 +489,7 @@ fn dir_list<P: AsRef<Path>>(dir: P) -> Vec<String> {
 /// So... we just manually handle these cases. So fucking fun.
 fn cross_runner() -> Option<String> {
     let runner = std::env::var("CROSS_RUNNER").ok()?;
-    if runner.is_empty() {
+    if runner.is_empty() || runner == "empty" {
         return None;
     }
     if cfg!(target_arch = "powerpc64") {
@@ -500,3 +510,17 @@ fn cross_runner() -> Option<String> {
 pub fn is_cross() -> bool {
     std::env::var("CROSS_RUNNER").ok().map_or(false, |v| !v.is_empty())
 }
+
+/// Strips absolutely fucked `<jemalloc>:` lines from the output.
+///
+/// In theory this only happens under qemu, which is where our tests run under
+/// `cross`. But is messes with our tests, because... they don't expect the
+/// allocator to fucking write to stderr. I mean, what the fuck? Who prints a
+/// warning message with absolutely no instruction for what to do with it or
+/// how to disable it. Absolutely fucking bonkers.
+fn strip_jemalloc_nonsense(data: &[u8]) -> Vec<u8> {
+    let lines = data
+        .lines_with_terminator()
+        .filter(|line| !line.starts_with_str("<jemalloc>:"));
+    bstr::concat(lines)
+}