fix(react-navigation): Make navigation.processing span title more explicit

[krystofwoldrich]

Based on feedback (in Slack) making the span title more expensive exactly describing what is being measured.

[antonis]

LGTM 🚀

[github-actions]

Android (legacy) Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	357.33 ms	457.72 ms	100.39 ms
Size	17.75 MiB	20.11 MiB	2.36 MiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
700cbf4	425.56 ms	436.26 ms	10.70 ms
d0bf494+dirty	375.37 ms	395.14 ms	19.77 ms
575f9da	415.26 ms	422.98 ms	7.72 ms
9433f35	347.64 ms	356.22 ms	8.58 ms
0ebca77	414.93 ms	444.49 ms	29.56 ms
e5c9b8b	409.02 ms	426.66 ms	17.64 ms
db44eaf	437.65 ms	436.06 ms	-1.59 ms
c639edf	466.48 ms	489.57 ms	23.09 ms
e1ea4a8	506.82 ms	510.48 ms	3.66 ms
8de2810	430.47 ms	428.72 ms	-1.75 ms

App size

Revision	Plain	With Sentry	Diff
700cbf4	17.73 MiB	20.07 MiB	2.33 MiB
d0bf494+dirty	17.73 MiB	19.75 MiB	2.02 MiB
575f9da	17.73 MiB	19.83 MiB	2.10 MiB
9433f35	17.73 MiB	19.81 MiB	2.08 MiB
0ebca77	17.73 MiB	19.95 MiB	2.21 MiB
e5c9b8b	17.73 MiB	19.83 MiB	2.10 MiB
db44eaf	17.74 MiB	20.08 MiB	2.35 MiB
c639edf	17.74 MiB	20.08 MiB	2.34 MiB
e1ea4a8	17.74 MiB	20.08 MiB	2.34 MiB
8de2810	17.74 MiB	20.08 MiB	2.34 MiB

[github-actions]

iOS (legacy) Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1242.46 ms	1238.33 ms	-4.13 ms
Size	2.63 MiB	3.68 MiB	1.05 MiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
e5bc97b+dirty	1230.63 ms	1234.83 ms	4.20 ms
205982c+dirty	1226.83 ms	1234.36 ms	7.53 ms
57448c5+dirty	1228.73 ms	1235.90 ms	7.16 ms
b1e8712+dirty	1256.02 ms	1265.14 ms	9.12 ms
946a600+dirty	1238.20 ms	1236.85 ms	-1.35 ms
b8ff156+dirty	1236.51 ms	1234.53 ms	-1.98 ms
0ebca77+dirty	1220.75 ms	1222.81 ms	2.06 ms
9385d74+dirty	1215.18 ms	1216.43 ms	1.25 ms
9dabcce+dirty	1231.39 ms	1238.02 ms	6.63 ms
690220d+dirty	1228.27 ms	1233.55 ms	5.29 ms

App size

Revision	Plain	With Sentry	Diff
e5bc97b+dirty	2.36 MiB	3.10 MiB	753.14 KiB
205982c+dirty	2.36 MiB	3.11 MiB	760.04 KiB
57448c5+dirty	2.36 MiB	3.10 MiB	752.34 KiB
b1e8712+dirty	2.36 MiB	2.84 MiB	488.84 KiB
946a600+dirty	2.36 MiB	3.10 MiB	759.74 KiB
b8ff156+dirty	2.36 MiB	3.11 MiB	759.80 KiB
0ebca77+dirty	2.36 MiB	3.04 MiB	698.33 KiB
9385d74+dirty	2.36 MiB	3.10 MiB	759.78 KiB
9dabcce+dirty	2.36 MiB	3.10 MiB	757.52 KiB
690220d+dirty	2.36 MiB	3.10 MiB	753.57 KiB

[antonis]

The failing End-to-End Tests / metrics (new, android) check is unrelated with this PR. See #4418

[github-actions]

iOS (new) Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1222.08 ms	1232.52 ms	10.44 ms
Size	3.19 MiB	4.25 MiB	1.06 MiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
e5bc97b+dirty	1229.17 ms	1227.64 ms	-1.54 ms
205982c+dirty	1228.06 ms	1237.72 ms	9.66 ms
57448c5+dirty	1244.65 ms	1249.20 ms	4.55 ms
b1e8712+dirty	1284.11 ms	1297.82 ms	13.71 ms
946a600+dirty	1236.12 ms	1234.94 ms	-1.18 ms
b8ff156+dirty	1238.92 ms	1239.57 ms	0.66 ms
0ebca77+dirty	1209.30 ms	1220.33 ms	11.03 ms
9385d74+dirty	1239.51 ms	1245.88 ms	6.37 ms
9dabcce+dirty	1247.71 ms	1239.18 ms	-8.53 ms
690220d+dirty	1227.45 ms	1221.67 ms	-5.78 ms

App size

Revision	Plain	With Sentry	Diff
e5bc97b+dirty	2.92 MiB	3.66 MiB	758.40 KiB
205982c+dirty	2.92 MiB	3.67 MiB	772.63 KiB
57448c5+dirty	2.92 MiB	3.66 MiB	756.65 KiB
b1e8712+dirty	2.92 MiB	3.40 MiB	494.15 KiB
946a600+dirty	2.92 MiB	3.67 MiB	772.40 KiB
b8ff156+dirty	2.92 MiB	3.67 MiB	772.38 KiB
0ebca77+dirty	2.92 MiB	3.61 MiB	705.12 KiB
9385d74+dirty	2.92 MiB	3.67 MiB	772.40 KiB
9dabcce+dirty	2.92 MiB	3.67 MiB	770.02 KiB
690220d+dirty	2.92 MiB	3.66 MiB	758.77 KiB