Observability i18n fixes (elastic#72984)

* Format `xpack.apm.percentOfParent` correctly so the transactions page in APM doesn't crash. In English it reads like, "(X% of transaction)". I'm not sure what the intention of the changed translation is, but I've changed it to be the equivalent of "(X% transaction)". A correction to the Japanese form here would be appreciated, but this fixes the crash and gets the message across.
* Format `xpack.infra.logs.customizeLogs.textSizeRadioGroup` correctly. This was not causing the whole logs page to crash, but was causing an error in the JS console.

x-pack/plugins/translations/translations/ja-JP.json

@@ -4247,7 +4247,7 @@
     "xpack.apm.metrics.transactionChart.transactionDurationLabel": "トランザクション時間",
     "xpack.apm.metrics.transactionChart.transactionsPerMinuteLabel": "1 分あたりのトランザクション数",
     "xpack.apm.notAvailableLabel": "N/A",
-    "xpack.apm.percentOfParent": "({parentType, select, transaction { 件中 {value} 件のトランザクション} トレース {trace} })",
+    "xpack.apm.percentOfParent": "({value} {parentType, select, transaction {トランザクション} trace {トレース} })",
     "xpack.apm.propertiesTable.agentFeature.noDataAvailableLabel": "利用可能なデータがありません",
     "xpack.apm.propertiesTable.agentFeature.noResultFound": "\"{value}\"に対する結果が見つかりませんでした。",
     "xpack.apm.propertiesTable.tabs.exceptionStacktraceLabel": "例外のスタックトレース",
@@ -7454,7 +7454,7 @@
     "xpack.infra.logs.customizeLogs.customizeButtonLabel": "カスタマイズ",
     "xpack.infra.logs.customizeLogs.lineWrappingFormRowLabel": "改行",
     "xpack.infra.logs.customizeLogs.textSizeFormRowLabel": "テキストサイズ",
-    "xpack.infra.logs.customizeLogs.textSizeRadioGroup": "{textScale, select, small {小さい} 中くらい {Medium} 大きい {Large} その他の {{textScale}} }",
+    "xpack.infra.logs.customizeLogs.textSizeRadioGroup": "{textScale, select, small {小さい} medium {中くらい} large {大きい} other {{textScale}}}",
     "xpack.infra.logs.customizeLogs.wrapLongLinesSwitchLabel": "長い行を改行",
     "xpack.infra.logs.emptyView.checkForNewDataButtonLabel": "新規データを確認",
     "xpack.infra.logs.emptyView.noLogMessageDescription": "フィルターを調整してみてください。",