Allow MultipartFormDataOutput to specify items with the same key #43087

Job	Run time
Attach pull request number	4s
CI Sanity Check	31s
Initial JDK 17 Build	14m 8s
Calculate Test Jobs	10s
Maven Tests - JDK 17	7m 53s
Maven Tests - JDK 17 Windows	12m 19s
Gradle Tests - JDK 17	28m 8s
Kubernetes Tests - JDK 17	12m 18s
Gradle Tests - JDK 17 Windows	48m 56s
JVM Tests - JDK 17	2h 50m 1s
Kubernetes Tests - JDK 21	11m 0s
JVM Tests - JDK 21	2h 52m 10s
Kubernetes Tests - JDK 17 Windows	20m 7s
JVM Tests - JDK 17 Windows	2h 52m 12s
Devtools Tests - JDK ${{ matrix.java.name }}	0s
Quickstarts Compilation - JDK 17	6m 32s
Native Tests - Main	6m 46s
MicroProfile TCKs Tests	11m 25s
Native Tests - Data1	31m 2s
Native Tests - Virtual Thread - Main	23m 53s
Native Tests - Data2	27m 22s
Native Tests - Virtual Thread - Messaging	9m 57s
Native Tests - Data3	21m 11s
Native Tests - Virtual Thread - Security	3m 20s
Native Tests - Data4	20m 58s
Native Tests - Data5	16m 40s
Native Tests - Data6	18m 39s
Native Tests - Data7	26m 59s
Native Tests - Amazon	15m 21s
Native Tests - Messaging1	24m 22s
Native Tests - Security2	16m 22s
Native Tests - Security3	11m 19s
Native Tests - Cache	14m 31s
Native Tests - HTTP	30m 31s
Native Tests - Misc1	11m 55s
Native Tests - Misc2	10m 12s
Native Tests - Misc3	22m 55s
Native Tests - Misc4	41m 16s
Native Tests - Spring	14m 10s
Native Tests - gRPC	16m 59s
Native Tests - Windows support	7m 14s
Upload build stats to collector	0s
Build report	40s
	18h 52m 28s

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