Add @babel/plugin-proposal-private-property-in-object to fix linter.

Fixes the following warning:

One of your dependencies, babel-preset-react-app, is importing the
"@babel/plugin-proposal-private-property-in-object" package without
declaring it in its dependencies. This is currently working because
"@babel/plugin-proposal-private-property-in-object" is already in your
node_modules folder for unrelated reasons, but it may break at any time.

babel-preset-react-app is part of the create-react-app project, which
is not maintianed anymore. It is thus unlikely that this bug will
ever be fixed. Add "@babel/plugin-proposal-private-property-in-object" to
your devDependencies to work around this error. This will make this message
go away.

package.json

@@ -130,6 +130,7 @@
   },
   "devDependencies": {
     "@babel/core": "^7.9.0",
+    "@babel/plugin-proposal-private-property-in-object": "^7.21.11",
     "@capacitor/cli": "^4.6.1",
     "@sinonjs/fake-timers": "^6.0.1",
     "@testing-library/dom": "^7.31.2",

yarn.lock

@@ -261,7 +261,7 @@
   dependencies:
     "@babel/types" "^7.14.5"
 
-"@babel/helper-annotate-as-pure@^7.22.5":
+"@babel/helper-annotate-as-pure@^7.18.6", "@babel/helper-annotate-as-pure@^7.22.5":
   version "7.22.5"
   resolved "https://registry.yarnpkg.com/@babel/helper-annotate-as-pure/-/helper-annotate-as-pure-7.22.5.tgz#e7f06737b197d580a01edf75d97e2c8be99d3882"
   integrity sha512-LvBTxu8bQSQkcyKOU+a1btnNFQ1dMAd0R6PyW3arXes06F6QLWLIrd681bxRPIXlrMGR3XYnW9JyML7dP3qgxg==
@@ -316,7 +316,7 @@
     "@babel/helper-replace-supers" "^7.14.5"
     "@babel/helper-split-export-declaration" "^7.14.5"
 
-"@babel/helper-create-class-features-plugin@^7.18.6", "@babel/helper-create-class-features-plugin@^7.24.1", "@babel/helper-create-class-features-plugin@^7.24.4":
+"@babel/helper-create-class-features-plugin@^7.18.6", "@babel/helper-create-class-features-plugin@^7.21.0", "@babel/helper-create-class-features-plugin@^7.24.1", "@babel/helper-create-class-features-plugin@^7.24.4":
   version "7.24.4"
   resolved "https://registry.yarnpkg.com/@babel/helper-create-class-features-plugin/-/helper-create-class-features-plugin-7.24.4.tgz#c806f73788a6800a5cfbbc04d2df7ee4d927cce3"
   integrity sha512-lG75yeuUSVu0pIcbhiYMXBXANHrpUPaOfu7ryAzskCgKUHuAxRQI5ssrtmF0X9UXldPlvT0XM/A4F44OXRt6iQ==
@@ -898,6 +898,16 @@
     "@babel/helper-plugin-utils" "^7.14.5"
     "@babel/plugin-syntax-private-property-in-object" "^7.14.5"
 
+"@babel/plugin-proposal-private-property-in-object@^7.21.11":
+  version "7.21.11"
+  resolved "https://registry.yarnpkg.com/@babel/plugin-proposal-private-property-in-object/-/plugin-proposal-private-property-in-object-7.21.11.tgz#69d597086b6760c4126525cfa154f34631ff272c"
+  integrity sha512-0QZ8qP/3RLDVBwBFoWAwCtgcDZJVwA5LUJRZU8x2YFfKNuFq161wK3cuGrALu5yiPu+vzwTAg/sMWVNeWeNyaw==
+  dependencies:
+    "@babel/helper-annotate-as-pure" "^7.18.6"
+    "@babel/helper-create-class-features-plugin" "^7.21.0"
+    "@babel/helper-plugin-utils" "^7.20.2"
+    "@babel/plugin-syntax-private-property-in-object" "^7.14.5"
+
 "@babel/plugin-proposal-unicode-property-regex@^7.14.5", "@babel/plugin-proposal-unicode-property-regex@^7.4.4":
   version "7.14.5"
   resolved "https://registry.npmjs.org/@babel/plugin-proposal-unicode-property-regex/-/plugin-proposal-unicode-property-regex-7.14.5.tgz"