[R/conditional_formatting] fix multiple databar entries per sheet

[JanMarvin]

Tested with:

library(openxlsx2)

wb <- wb_workbook()
wb$add_worksheet("databar")
## Databars
wb$add_data("databar", -5:5, startCol = 1)
wb_conditional_formatting(
  wb,
  "databar",
  cols = 1,
  rows = 1:11,
  type = "databar"
) ## Default colours

wb$add_data("databar", -5:5, startCol = 3)
wb_conditional_formatting(
  wb,
  "databar",
  cols = 3,
  rows = 1:11,
  type = "databar",
  showValue = FALSE,
  gradient = FALSE
) ## Default colours

wb$add_data("databar", -5:5, startCol = 5)
wb_conditional_formatting(
  wb, 
  "databar",
  cols = 5,
  rows = 1:11,
  type = "databar",
  style = c("#a6a6a6"),
  showValue = FALSE
)

wb$add_data("databar", -5:5, startCol = 7)
wb_conditional_formatting(
  wb,
  "databar",
  cols = 7,
  rows = 1:11,
  type = "databar",
  style = c("red"),
  showValue = TRUE,
  gradient = FALSE
)

wb$add_data("databar", -5:5, startCol = 9)
wb_conditional_formatting(
  wb,
  "databar",
  cols = 9,
  rows = 1:11,
  type = "databar",
  style = c("#a6a6a6", "#a6a6a6"),
  showValue = FALSE, 
  gradient = FALSE
)

wb$open()

[codecov-commenter]

Codecov Report

Merging #174 (f5107cc) into main (437eb13) will increase coverage by 0.22%.
The diff coverage is 97.91%.

@@            Coverage Diff             @@
##             main     #174      +/-   ##
==========================================
+ Coverage   77.52%   77.74%   +0.22%     
==========================================
  Files          36       36              
  Lines        7342     7424      +82     
==========================================
+ Hits         5692     5772      +80     
- Misses       1650     1652       +2     

Impacted Files	Coverage Δ
R/class-workbook.R	73.83% <94.73%> (+0.11%)	⬆️
R/pugixml.R	100.00% <100.00%> (ø)
src/pugi.cpp	100.00% <100.00%> (ø)
src/openxlsx2_types.h	100.00% <0.00%> (ø)
R/wb_functions.R	88.11% <0.00%> (+0.02%)	⬆️
R/wb_load.R	94.69% <0.00%> (+0.10%)	⬆️
src/load_workbook.cpp	92.46% <0.00%> (+0.21%)	⬆️
src/write_file.cpp	94.23% <0.00%> (+1.59%)	⬆️

---

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[JanMarvin]

Another option would have been to select the xml_nodes for x14:conditionalFormatting, combine them in a new x14:conditionalFormattings and replace this node inside the extLst using something like this: 2ead3d1