[highlight] turn off nesting for var highlight

src/textfile_highlighters.cc

@@ -429,6 +429,7 @@ setup_highlights(highlight_map_t& hm)
                             "(?<!\\$)\\$\\((\\w+)\\)|"
                             "(?<!\\$)\\$\\{(\\w+)\\}"
                             ")"))
+              .with_nestable(false)
               .with_role(role_t::VCR_VARIABLE);
     hm[{highlight_source_t::INTERNAL, "rust.sym"}]
         = highlighter(xpcre_compile("\\b[A-Z_][A-Z0-9_]+\\b"))

test/expected/test_pretty_print.sh_3c255c3c8b28df9d694b329a265e8b8140dae4a2.out

@@ -1,7 +1,7 @@
 {
     "wrapper": [
             {"message":""
-            select Id from Account where id = $sfid
+            select Id from Account where id = $sfid
                                              ^
             ERROR at Row:1:Column:34
             line 1:34 no viable alternative at character '$'

test/expected/test_text_file.sh_5b51b55dff7332c5bee2c9b797c401c5614d574a.out

@@ -1,17 +1,17 @@
 Build[1][2] Docs[3][4] Coverage Status[5][6] lnav[7][8]
 
  ▌[1] - https://github.com/tstack/lnav/workflows/ci-build/badge.svg               
- ▌[2] - https://github.com/tstack/lnav/actions?query=workflow%3Aci-build          
- ▌[3] - https://readthedocs.org/projects/lnav/badge/?version=latest&style=plastic 
+ ▌[2] - https://github.com/tstack/lnav/actions?query=workflow%3Aci-build          
+ ▌[3] - https://readthedocs.org/projects/lnav/badge/?version=latest&style=plastic 
  ▌[4] - https://docs.lnav.org                                                     
- ▌[5] - https://coveralls.io/repos/github/tstack/lnav/badge.svg?branch=master     
- ▌[6] - https://coveralls.io/github/tstack/lnav?branch=master                     
+ ▌[5] - https://coveralls.io/repos/github/tstack/lnav/badge.svg?branch=master     
+ ▌[6] - https://coveralls.io/github/tstack/lnav?branch=master                     
  ▌[7] - https://snapcraft.io/lnav/badge.svg                                       
  ▌[8] - https://snapcraft.io/lnav                                                 
 
 <img
-src="https://assets-global.website-files.com/6257adef93867e50d84d30e2/62594fddd654fc29fcc07359_cb48d2a8d4991281d7a6a95d2f58195e.svg"
-height="20"/>[1]
+src="https://assets-global.website-files.com/6257adef93867e50d84d30e2/62594fddd654fc29fcc07359_cb48d2a8d4991281d7a6a95d2f58195e.svg"
+height="20"/>[1]
 
  ▌[1] - https://discord.gg/erBPnKwz7R 
 
@@ -97,11 +97,11 @@ output those messages still in a non-binary representation:
 If using systemd v236 or newer, the output fields can be limited to
 the ones actually recognized by  lnav  for increased efficiency:
 
- ▌$ journalctl -o json --output-fields=MESSAGE,PRIORITY,_PID,SYSLOG_IDENTIFIER,_SYSTEMD_UNIT | lnav    
+ ▌$ journalctl -o json --output-fields=MESSAGE,PRIORITY,_PID,SYSLOG_IDENTIFIER,_SYSTEMD_UNIT | lnav    
 
 If your system has been running for a long time, for increased
 efficiency you may want to limit the number of log lines fed into  lnav
-, e.g. via  journalctl 's  -n  or  --since=...  options.
+, e.g. via  journalctl 's  -n  or  --since=...  options.
 
 In case of a persistent journal, you may want to limit the number of
 log lines fed into  lnav  via  journalctl 's  -b  option.

test/expected/test_text_file.sh_6a24078983cf1b7a80b6fb65d5186cd125498136.out

@@ -68,11 +68,11 @@ output those messages still in a non-binary representation:
 If using systemd v236 or newer, the output fields can be limited to
 the ones actually recognized by  lnav  for increased efficiency:
 
- ▌$ journalctl -o json --output-fields=MESSAGE,PRIORITY,_PID,SYSLOG_IDENTIFIER,_SYSTEMD_UNIT | lnav    
+ ▌$ journalctl -o json --output-fields=MESSAGE,PRIORITY,_PID,SYSLOG_IDENTIFIER,_SYSTEMD_UNIT | lnav    
 
 If your system has been running for a long time, for increased
 efficiency you may want to limit the number of log lines fed into  lnav
-, e.g. via  journalctl 's  -n  or  --since=...  options.
+, e.g. via  journalctl 's  -n  or  --since=...  options.
 
 In case of a persistent journal, you may want to limit the number of
 log lines fed into  lnav  via  journalctl 's  -b  option.

test/expected/test_text_file.sh_e088ea61a5382458cc48a2607e2639e52b0be1da.out

@@ -68,11 +68,11 @@ output those messages still in a non-binary representation:
 If using systemd v236 or newer, the output fields can be limited to
 the ones actually recognized by  lnav  for increased efficiency:
 
- ▌$ journalctl -o json --output-fields=MESSAGE,PRIORITY,_PID,SYSLOG_IDENTIFIER,_SYSTEMD_UNIT | lnav    
+ ▌$ journalctl -o json --output-fields=MESSAGE,PRIORITY,_PID,SYSLOG_IDENTIFIER,_SYSTEMD_UNIT | lnav    
 
 If your system has been running for a long time, for increased
 efficiency you may want to limit the number of log lines fed into  lnav
-, e.g. via  journalctl 's  -n  or  --since=...  options.
+, e.g. via  journalctl 's  -n  or  --since=...  options.
 
 In case of a persistent journal, you may want to limit the number of
 log lines fed into  lnav  via  journalctl 's  -b  option.