Refactored most of the CLI tests to run in-process as opposed to using sub-processes (#1059)

* cli: fixed remaining testability indirections for output and logging

* cli: added cli.RunSubcommand() which is used in testing to execute a subcommand in the same process

* tests: refactored most e2e tests to invoke kopia subcommands in-process

* Makefile: enable code coverage for cli/ and internal/

* testing: pass 'testing' tag to unit tests which uses much faster (insecure) password hashing scheme

* Makefile: push coverage from PRs again

* tests: disable buffer management to reduce memory usage on ARM

* cli: fixed misaligned atomic field on ARMHF

also temporarily fixed statup-time benign race condition when setting
default on the timeZone variable, which is the last global variable.

cli/command_ls.go

@@ -113,7 +113,7 @@ func (c *commandList) printDirectoryEntry(ctx context.Context, e fs.Entry, prefi
 		info = fmt.Sprintf("%v%v", c.nameToDisplay(prefix, e), errorSummary)
 	}
 
-	col.Println(info) //nolint:errcheck
+	col.Fprintln(c.out.stdout(), info) //nolint:errcheck
 
 	if c.recursive {
 		if subdir, ok := e.(fs.Directory); ok {