I wrote a board file (copied from readnow.exp) setting editing to off by default:
...
$ cat gdb/testsuite/boards/editing-off.exp 
  ...
load_board_description "local-board"

# Run all tests with editing off.
set GDBFLAGS "${GDBFLAGS} -iex \"set editing off\""

# This is based on baseboards/unix.exp.
# At the moment we only support systems that unix.exp supports.
load_generic_config "unix"
process_multilib_options ""
set found_gcc [find_gcc]
set found_gxx [find_g++]
set_board_info compiler "$found_gcc"
...

Results:
...
FAIL: gdb.ada/access_to_packed_array.exp: set logging enabled on (timeout)
FAIL: gdb.ada/access_to_packed_array.exp: maint print symbols (timeout)
FAIL: gdb.base/page-logging.exp: set logging enabled on (timeout)
FAIL: gdb.base/page-logging.exp: printf without paging (timeout)
FAIL: gdb.base/trace-commands.exp: nested trace-commands test (pattern 2)
FAIL: gdb.base/trace-commands.exp: depth resets on error part 1 (pattern 2)
FAIL: gdb.base/ui-redirect.exp: redirect: set logging enabled on (timeout)
FAIL: gdb.base/ui-redirect.exp: redirect: save breakpoints cmds.txt (timeout)
FAIL: gdb.base/ui-redirect.exp: redirect: userdefined (timeout)
FAIL: gdb.base/ui-redirect.exp: redirect logging and debuging: set logging enabled on (timeout)
FAIL: gdb.python/tui-window-factory.exp: msg_3: check for python output
FAIL: gdb.threads/threadapply.exp: thread_set=all: try remove: define remove (timeout)
FAIL: gdb.threads/threadapply.exp: thread_set=all: try remove 2: define remove-again (timeout)
FAIL: gdb.tui/basic.exp: scroll up
FAIL: gdb.tui/basic.exp: check main is where we expect on the screen
FAIL: gdb.tui/basic.exp: scroll right
FAIL: gdb.tui/basic.exp: scroll down
FAIL: gdb.tui/basic.exp: asm window shows main
FAIL: gdb.tui/completion.exp: check focus completions
FAIL: gdb.tui/info-win.exp: info win, layout src
FAIL: gdb.tui/info-win.exp: info win, layout h
FAIL: gdb.tui/new-layout.exp: layout=cmd_only {cmd 1} {} {}: info win output
FAIL: gdb.tui/scroll.exp: check cmd window
FAIL: gdb.tui/scroll.exp: check cmd window in flip layout
FAIL: gdb.tui/tui-focus.exp: check test2 focus message
FAIL: gdb.tui/tui-focus.exp: check ambiguous focus message
FAIL: gdb.tui/tui-layout-asm.exp: scroll to end of assembler (scroll failed)
FAIL: gdb.tui/tui-nl-filtered-output.exp: check printf output
FAIL: gdb.tui/winheight.exp: check error message about src size 100
FAIL: gdb.tui/winheight.exp: check error message about src +1
...

Related PRs:
- PR22454 - "logging sometimes prints prompt"
- PR30288 - "[gdb/cli, editing off] FAIL: gdb.base/trace-commands.exp: nested
  trace-commands test (pattern 2)"