[ota-provider-app] fix location parsing and BDX sender

[holbrookt]

Problem

This PR contains necessary changes for completing an OTA BDX transfer with an ota-requestor-app (which will also require changes submitted in another PR).

• file I/O for BDX sending was erroring out on EOF instead of sending the last block
• code that verified QueryImage parameters was using emberAfStringLength() which is incompatible with CHIP TLV format
• The BDX ExchangeContext was closing after every message send
• Fixes Fix QueryImage param length checking #9703

Change overview

• don't consider EOF as an error condition when reading blocks for BDX transfer
• don't keep calling gcount() to get the number of bytes read
• add kExpectResponse for all BDX messages except StatusReport in order to keep exchange open
• use strlen() to parse location string instead of emberAfStringLength()
• fix message for printing location string length

Testing

• tested again modified ota-requestor-app (PR will be submitted soon)

[github-actions]

Size increase report for "esp32-example-build" from 4763c91

File	Section	File	VM
chip-all-clusters-app.elf	.flash.text	4	4

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-all-clusters-app.elf and ./pull_artifact/chip-all-clusters-app.elf:

sections,vmsize,filesize
.debug_abbrev,0,24
.debug_line,0,4
.flash.text,4,4
[Unmapped],0,-4
.debug_loc,0,-7
.debug_info,0,-97

[woody-apple]

@saurabhst @Damian-Nordic @LuDuda ?