change --hint[X] => --hint:X in nim repo (avoids shell quoting issues) (#18085)

tests/effects/toutparam.nim

@@ -1,5 +1,5 @@
 discard """
-  cmd: '''nim c --warningAsError[Uninit]:on --skipCfg --skipParentCfg $file'''
+  cmd: '''nim c --warningAsError:Uninit:on --skipCfg --skipParentCfg $file'''
   errormsg: "use explicit initialization of 'x' for clarity [Uninit]"
   line: 24
   disabled: "true"

tests/osproc/treadlines.nim

@@ -13,7 +13,7 @@ var ps: seq[Process] # compile & run 2 progs in parallel
 const nim = getCurrentCompilerExe()
 for prog in ["a", "b"]:
   ps.add startProcess(nim, "",
-                      ["r", "--hint[Conf]=off", "--hint[Processing]=off", prog],
+                      ["r", "--hint:Conf:off", "--hint:Processing:off", prog],
                       options = {poUsePath, poDaemon, poStdErrToStdOut})
 
 for p in ps:

tests/pragmas/t8741.nim

@@ -1,5 +1,5 @@
 discard """
-  cmd: "nim check --hint[processing]:off $file"
+  cmd: "nim check --hint:processing:off $file"
   errormsg: "3 is not two"
   nimout: '''t8741.nim(13, 9) Error: cannot attach a custom pragma to 'a'
 t8741.nim(29, 15) template/generic instantiation of `onlyTwo` from here

tests/range/tcompiletime_range_checks.nim

@@ -1,5 +1,5 @@
 discard """
-  cmd: "nim check --hint[Processing]:off --hint[Conf]:off $file"
+  cmd: "nim check --hint:Processing:off --hint:Conf:off $file"
   errormsg: "18446744073709551615 can't be converted to int8"
   nimout: '''tcompiletime_range_checks.nim(36, 21) Error: 2147483648 can't be converted to int32
 tcompiletime_range_checks.nim(37, 23) Error: -1 can't be converted to uint64

tests/tools/tunused_imports.nim

@@ -1,5 +1,5 @@
 discard """
-  cmd: '''nim c --hint[Processing]:off $file'''
+  cmd: '''nim c --hint:Processing:off $file'''
   nimout: '''
 tunused_imports.nim(11, 10) Warning: BEGIN [User]
 tunused_imports.nim(36, 10) Warning: END [User]